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Blog

Thanks again to everyone who joined us for last week’s webinar “Top 5 Low Cost Tips for Preventing Exchange Downtime” where Marathon’s availability experts reviewed their key tips for the prevention of downtime, including:

1. Reduce human error with process
2. Document your infrastructure
3. Remove single points of failure
4. Don’t forget to test
5. Understand your requirements

There’s a lot of great information in this 40-minute webinar, so be sure to check it out. We’ve summarized the Q&A portion for the webinar below.
 

Q: What type of storage does everRun support?
everRun supports any type of storage that you have. The most common storage configuration we see is local disk drives for the servers themselves. That would have the same amount of data protection as even a SAN would, and in some cases would be even better protection, because you have total redundancy from both servers and everRun is protecting that as if it’s a single storage device. You could also have iSCSI connected storage, or any kind of SAN storage that you wanted to have. Again, everRun supports any type of storage.

Q: Which versions of Exchange do you support?
The beauty of the everRun architecture is that is can support pretty much any Windows-based application. Exchange 2003, Exchange 2007 or Exchange 2010 – everRun supports them all. Some other high availability solutions require specialized scripting to support applications, but everRun does not require this. Also, with solutions like clusters, sometimes you have to buy the higher-end more expensive “enterprise” versions of the application software to support that configuration, but with everRun, we can provide complete protection for the standard versions of Windows and Exchange Server or any other application.

Q: What is the load on the systems when using everRun?
The good news here is that there is very little overhead associated with everRun – about 5% to make things run redundantly. That’s a very small performance price to pay to get such a high level of protection for Exchange.

Q: How does everRun handle the mirroring of data that’s loaded in memory?
There are a couple of ways that is done. Since the application is actually running both severs simultaneously, that means the memory is being replicated on both servers simultaneously as well. Keep in mind that as the applications execute, they are storing to storage, and because of the redundancy built into the everRun solution, that data is being written from memory down under the storage element redundantly as well.

Q: Is it possible to run servers in two different locations?
Absolutely. In the slide where I showed the everRun architecture with the two servers, you can take those two servers and separate them geographically. They could be in different rooms in the same building, different buildings on the same campus, or even separated further, by about 100 miles, depending on the bandwidth and latency of your connection. We call this our SplitSite configuration.

Q: How is this different from a cluster solution?
The major difference of everRun vs. a cluster solution is that we are doing operations on two servers simultaneously. The application is actually running in tandem on both of these servers. With a cluster solution, you’re running your application on one server, while the other server stands by and waits for a failure to occur. That means that with a cluster solution, when the first server fails, the cluster then has to do something to start up the application on the second server and then continue from that point. But that means downtime, data loss, and loss of connectivity. With everRun, that doesn’t happen. Because the other server is already doing the same thing, there is no downtime and no data loss, because there is no “recovery” – even when there is a failure.

Q: So are both servers “hot” in an everRun configuration?
Yes – that’s exactly right. Both servers are active and run simultaneously, unlike a cluster. So with everRun, you could have a failure of a component on one server and then another type of failure on the second server and still be operational. With a cluster, this scenario is not possible. If you have failures on both systems at the same time with a cluster, then you are down.

Q: Does everRun require dedicated servers just for Exchange?
No – everRun protected servers do not need to be dedicated to one specific application. You can run multiple applications on this pair of servers, and even chose which ones you do or don’t want to protect with everRun. This is good for small businesses, who want or need to consolidate several applications on to fewer servers.

For more information about protecting Exchange from downtime, be sure to check out our white paper "Six Secrets to 24x7 Exchange Availability."
 

Frank Ohlhorst, former Executive Technical Editor for eWeek and award-winning IT expert, was our expert guest speaker this week for the webinar, “Cut Your DR Costs and Get Better Data Protection.” During his presentation, Frank reviewed why he believes that now is the time to rethink traditional approaches to disaster recovery. He explained why the total cost of ownership for disaster recovery solutions is on the rise, and why changing data protection dynamics are making it more economical to focus your time and budget on the prevention of downtime and data loss, rather than recovery.

Below is the summary of the audience questions from the Q&A portion of the webinar.

Q: You talked about how HA can give you a geographic advantage. What do you mean by that?
Frank Ohlhorst: High availability systems are designed to work with multiple servers and there’s no reason why you can’t have those servers located hundreds or thousands of miles apart. You get a geographic advantage because your data centers is in multiple places and regional areas, so if a weather-related or other event occurs, let’s say a blizzard up north with a power outage, your data center down south can pick up the slack without kicking users off the system. The same can be said about a data center located in an area with hurricanes or other natural disasters. The geographic separation gives you added protection.
When high availability is paired with load balancing, it helps to locate the data resources closer to where the users are requesting them. Let’s say you have users in Utah, it’s better performance-wise to have them talk to the data center in Nevada rather than Virginia. It helps on that level also. HA solutions also have the tools for monitoring what is going on with your users and network, to help you plan out how you should assign users to specific data centers for the most efficiency.

Q: I understand how high availability can handle unplanned downtime, but what about planned downtime? Can it help there as well?
Frank Ohlhorst: Yes, the idea there is being as you have multiple active systems to meet the user’s needs, you can take one of those systems down for maintenance and have the users serviced by the active machines while you make the updates and improvements. Then when you are done, just resynchronize with the other systems, move the users over to those systems and update the rest of the servers.
Another great benefit of this is for testing upgrades and changes. So take one system offline and test your upgrades to see if they work properly before you return that system to production.

Q: If I have an HA solution in place, is back-up still necessary?
Frank Ohlhorst: 99% of the time the answer to that question is yes. It depends on what your corporate needs are. There are certain situations where HA might not deal with your catastrophe. Those are usually software-damaging events, like a virus infection, that winds up getting replicated across the system. Of course, that should really be part of your security planning to prevent events like that from even happening. With today’s security technologies, it’s pretty easy to prevent that. But if you did ever have one of those events, you do need something to roll-back to, and that’s where the back-up comes in to play. Ideally though, you should be preventing that type of event, because you also have the potential to lose active data if that happens. When it comes to compliance or auditing, you have to restore data relevant to that time period to meet the needs of e-discovery, compliance, accounting audits and other similar requirements. So you can’t just say, “I have HA in place, so I don’t need to back-up.”

Q: What about data de-duplication technologies, don’t they help solve this problem of managing large volumes of data?
Frank Ohlhorst: They reduce the data footprint for sure, but what we’re talking about here is availability of the data. They can certainly reduce the size of your data footprint, you can use de-dup to speed up backups. At the end of the day though, if the system or application is not accessible to the user, then it’s not available and you haven’t met your objectives. It’s a simple matter of business logic that data de-duplication can improve performance and reduce the size of the footprint, but it doesn’t solve the problem of providing access to users during catastrophic events.

Q: Do you see continuous availability and high availability as the same, and if so, how do you differentiate between the two and the costs?
Frank Ohlhorst: There was a time when those technologies were very, very different. That was way back when we relied on expensive hardware-based solutions or appliances that provided continuous availability. High availability at that time was thought of as a method to switch from one server to another using a manual process in the case of an emergency.

High Availability technology has evolved significantly since then. Now, the two are really one in the same from a planning and software point of view. Today’s HA solutions eliminate that step of manual switchover. What you see with the vendors today is automatic HA technology that really delivers continuous availability. And the cost gap today is pretty much zero, since the technology for continuous availability and high availability has evolved to be almost one in the same.

Q: With an SRDF/S-type solution, how can we get around the fact that being geographically more separated to mitigate regional disruptions can mean slower primary system response times due to the need to remain synchronous?
Frank Ohlhorst: Let’s look at this first from the ideology of what we’re trying to do which is business continuity. So, if you encounter a situation when you lose connectivity to a system and it’s still available at another location, then you’ve met the goal there of providing continuity. And you’re in much better shape than you would be at that point if you had a disaster recovery solution instead of a business continuity solution.

The question you have to ask yourself at that point in time is: Is reduced performance better than no performance at all? For most businesses, the answer is yes. For others, if the performance lag is significant enough it can impact business. In those cases, you’ll have to work out a way to develop geographically dispersed sites can that can provide enough performance to the user sets that need access to the data. You also need to make sure that your connectivity has enough bandwidth to support your BC/HA solutions, which means the ability to replicate the data in real time across the wire. You might have to invest in larger pipes for better connectivity to support that. But again, that depends on your particular business and your needs. There is no one correct answer to this question, but the good news is that there are several solutions today that can help you solve this problem and meet the levels of availability that you need for your business.

Next week Craig Resnick, research director and automation expert at ARC Advisory Group will be the guest speaker for our webinar "Best Practices for Preventing Downtime in Automation Systems."  We recently sat down with Craig to discuss some of the recent trends in the manufacturing and automation industries.

Q: What are some of the newer trends that you are seeing in the automation space?

Craig Resnick: A primary trend that we see at ARC is the convergence of automation and IT systems. Nearly every manufacturing company uses a variety of plant automation and enterprise IT systems to manage its operations. Plant floor systems, such as distributed control systems (DCS), programmable automation and logic controllers (PACs/PLCs), and a wide range of plant floor applications provide a wealth of real-time information regarding productivity, efficiency, equipment health, capability, and quality. Business systems, in turn, provide information on raw material costs, product orders and inventories, manufacturing resources, production schedules, etc. This wide range of information often remains isolated in systems such as manufacturing execution systems (MES), laboratory systems, maintenance systems, scheduling systems, enterprise resource planning (ERP) systems, supply chain management (SCM) systems, and customer relationship management (CRM) systems. Decisions based on data from any one of these system will always be less than optimal because, without the corresponding information from the other systems, the information will be incomplete.

To close this gap between automation and IT systems, and to address the trend of the plant floor becoming more IT-centric, ARC has defined a new space, defined as Collaborative Production Systems. These new systems consist of platforms in which the controls layer domains of process, logic, motion, building automation, and power control systems converge with the information layer domains of production management and MES systems. These converged systems enable, for example, the required data and information to be directly tied into applications such as corporate reporting and manufacturing compliance. Collaborative Production Systems will become the industrial blade server that provides full monitoring and control of the enterprise, from the office to the plant floor, sharing that information with the supply chain to, for example, procure materials and resources and purchase or sell power at the optimal times and prices from the smart grid, while providing full financial metrics and KPIs to ERP systems to maximize profitability.

Q: Now that corporate reporting and systems are heavily tied into the “factory floor”, how is that changing the need for system availability and data protection?

Craig Resnick: The need for system availability and data protection continues to expand, driven by a combination of issues ranging from global competition to regulatory requirements. Process safety and critical control are primarily focused on system availability and process uptime. As a specific example, take the Pharmaceutical industry, where data and batch information can never be lost or interrupted. System availability and data protection needs are also forcing E-records regulations to evolve across the globe. In the US, this includes 21 CFR Part 11, as well as the FDA’s Good Manufacturing Practice (GMP) and Process Analytical Technology (PAT) initiatives. In Europe, this includes Annex 11 of the EU GMPs, electronic Signatures Directive 1999/93/EC, and Data Protection Directive 95/46/EC. The European Data Protection Directive requires even more protection on data than the current FDA regulations and extends this requirement to clinical trials patients, as all clinical trials data requires maximum protection to remain compliant with regulations.

Unscheduled downtime is expensive. It often impacts production’s ability to meet its schedule and may cause missed customer commitments. Unplanned downtime, which also includes unexpected stoppages resulting from equipment failure, operator error, or nuisance trips, is the nemesis of all manufacturers. Statistics on the impact of unplanned downtime on plant operations show that it accounts for 2 to 5 percent of production lost in, for example, the petrochemical industry. Unscheduled downtime is also costly in terms of equipment damage, environmental harm, and worker safety. The cost of downtime is reflected in a primary key performance indicator (KPI) used by manufacturers known as Dynamic Overall Equipment Effectiveness (OEE), which helps determine the real-time impact of the performance of any individual process or piece of equipment on the overall efficiency of the plant. Unscheduled downtime is a primary factor that significantly lowers Dynamic OEE, which translates to the manufacturer decreasing both its efficiency and profitability.

Q: What are some of the basic steps that companies can implement to ensure the availability of their systems?

Craig Resnick: The first step that companies can implement to ensure the availability of their systems is to maximize their operator’s effectiveness in the control room, which is essential to minimize the risks of accidents, eliminate unscheduled downtime, and maximize production quality. The global process industry loses $20 billion, or five percent of annual production, due to unscheduled downtime and poor quality. ARC estimates that almost 80 percent of these losses are preventable and 40 percent of those preventable losses are primarily the result of human or operator error. Maximizing operator effectiveness requires automating as many functions as technology will allow, as well as reducing complexity wherever possible. For example there are still many plants where operators monitor the processes and collect data manually or semi-automatically using chart recorders. This process is both tedious and error prone, and does not provide appropriate process insight or instill a sense of ownership among the control room operators.

The Abnormal Situation Management Consortium (ASM) points out that most incidences occur from multiple modes of failure. Preventable human error is a contributing factor to these losses, but is hardly the only cause. Preventing abnormal situations requires a multilayered multi-discipline approach focused on maximizing production throughput, efficiency and quality while minimizing lost production time and preventing damage to assets and endangerment to personnel. This approach requires deploying collaborative production systems designed and implemented to be able to deliver high levels of availability and fault-tolerance expected from any other mission critical industrial system. This typically requires effective data backup mechanisms, redundant controllers for critical applications, plus industrial grade software. Manufacturers are also deploying more fault tolerant server technology to ensure continuous availability of these mission critical applications; the continuous flow of vital products to the market; and the avoidance of the potentially negative financial, social, or environmental impact that operating without high availability fault-tolerant systems might bring.

To learn more about preventing downtime in your automation applications, be sure to attend next week's webinar where Craig will provide expert info on steps for reducing the human error that leads to downtime, how to protect your hardware, storage and networks for complete availability coverage, and how to protect against a complete site failure. You can register here.
 

Last Thursday’s webinar “Application Availability for Remote & Branch Locations” with Forrester analyst Stephanie Balaouras was packed with useful tips and best practices for protecting remote and branch offices from application service disruption. Stephanie has conducted extensive research in this area and shared her Top 5 Best Practices during the webinar. A recording of the webinar is now available in case you missed the live event.

The summary of the webinar Q&A with Stephanie and Michael Bilancieri, Sr. Director of Products for Marathon, is below.

Q: I like the idea of integrating HA and DR plans. How often should those plans be updated?
A: Stephanie Balaouras, Forrester: The ideal scenario is to update your high availability and disaster recovery plans continuously as part of your change management and configuration management. That’s the ideal scenario. They should be integrated into day-to-day operations and your plans should be updated as a part of that. If that’s not feasible, then at least quarterly updates should be made to the plans. One of the hardest parts of DR is that if you don’t keep the plans updated and you’re not testing regularly you’ll have major configuration drift between your sites. When you have a failure or disaster and have to invoke your DR plan is not the time you want to find out just how far your configurations have drifted and that you can’t recover. One solution for this is the combination of virtualization and replication, which can reduce complexity because in most cases you’re actually replicating the configuration changes as they happen.

Q: On your disaster recovery continuum slide (slide #14), can I think of that as a disaster recovery maturity model?
A: Stephanie Balaouras, Forrester: Not really. When I evaluate a company for disaster recovery maturity, I look at two dimensions – process and technology.

On the process side, I look at things such as: Have you run a business impact analysis? What about a risk assessment? Are preventative measures in place? Do you have documented plans, and are they up to date? How often do you test them?

On the technology side, I look at things like the RTO and RPO that you have defined: Are they matched up with the appropriate technology solution? If RTO is less than 2 hours and RPO is zero then I would expect that you are replicating data and doing rapid system restart with virtualization. If I find that you are using tape in that situation, then that’s a problem. I think when it comes to maturity you have to look at process and technology together. Not only should you match up with the right technology, but you might actually leverage more than one technology depending on your needs.

Q: Traditionally, HA & DR at remote locations has not been a priority. Do you see that attitude changing with clients that you talk to?
A: Stephanie Balaouras, Forrester: I do see things changing. I run an annual survey with the Disaster Recovery Journal. One of the questions we ask is: How critical is it to upgrade disaster recovery at your sites? The answer is always either “high” to “extremely critical”. It doesn’t always get addressed the way we want it to, but the recognition is there.

I see three main drivers for this trend. First, availability and disaster recovery are now considered a fiduciary responsibility. It’s no longer an optional practice. It’s essential. It’s something you owe to your employees, your customers, your partners and your investors. Second is the cost of downtime. Companies are much savvier at calculating this cost and aware of the problems they can avoid by not having downtime. When you understand those costs, you can make the right technology investment choices. The final driver I see is the changing business environment. A lot of companies are operating globally on a near 24x7 basis. Like an online retailer for example. We’re operating close to 24x7 and there is no tolerance for downtime anymore. All three of these – fiduciary responsibility, cost of downtime and a 24x7 business environment are moving the needle quite a bit.

Q: In my environment, our IT staff says they have no way to measure if an application is up or not. They can tell us if a server is up, or if a database is up, but not the application. What solutions have you seen that can tackle that issue?
A: Stephanie Balaouras, Forrester: There’s a couple of ways to address that. There are third party application monitoring tools from the large system vendors. They are great for basic monitoring and telling you if your application is up or down, but they don’t tell you about degradation of performance. The other option is that different HA solutions will be able to detect whether the applications is up or down.

Michael Bilancieri, Sr. Director of Products for Marathon, answered your questions about everRun software.

Q: Does everRun have any kind of alerting capabilities for system problems?
A: Yes, everRun has alerts. You can send notifications back to any location. It will tell you that something has failed – it’s not a downed system because everRun kept it going through redundancy, but it alerts you that it needs attention.

Q: Does everRun require that the two servers to be identical?
A: The servers don’t have to be exactly the same; however, the CPUs should be identical as a best practice. For what we call our Level 2 protection (for component level protection of the network and disk), you can use different RAM and spindle speeds on storage. Level 3 protected workloads require the servers to be alike. You can view a complete list of supported processors on our website.

Q: How much of CPU and IO payload will we have by running the everRun software?
A: It varies depending on the applications and systems and where the load may be. The general range is from 5-10%. We have specific application performance documentation for Exchange 2007 and XenApp that you can download from our website.

Q: I understand from your presentation that everRun doesn’t require a SAN, but does it work with SAN?
A: everRun can support a SAN in multiple ways. everRun can support a SAN where you have a single copy of the data. And both servers will connect to the single copy of the data. everRun also supports a SAN where one of the servers is connected to that SAN and the other server has its own storage and we can mirror between that. A lot of our customers are using that option to provide data protection and fault tolerance at the data level. We can use different types of storage on either side.
A great benefit of everRun is that is has an agnostic approach to storage. Pretty much any type of storage will work. iSCSI, fiber, direct attached, etc.

Q: Does Marathon have a strategy for SAP environments?
A: Applications are transparent to everRun. We protect many types of SQL, Oracle and SAP applications. There are some best practices around that and we can offer you assistance with those. everRun is invisible to the application, so there are no configuration and design issues. You design your application the way you need to for your business and then everRun protects it without needing changes.

Q: What versions of Windows Server does everRun support?
A: everRun supports Windows Server 2003 SP2 Standard and Enterprise Editions, 32-bit and 64-bit, as well as Windows Server 2008 Standard and Enterprise Editions, 64-bit.

Q: The requirement for redundant systems is obvious, one local and one remote, but I am concerned with the return of the repaired server back to the primary server role. Has that issue been also automated in your application?

A: Replacing one of the servers in an everRun configuration is quite simple as well. It is required that the everRun software be installed and the server be physically connected to the remaining everRun system. Once connected and configured to see each other as a pair, there is a ‘re-pairing’ process that is initiated via command which starts the process of creating the redundant OS environment on the new system and mirroring all of the storage to the new system. Once the mirroring is complete, the system is once again fully protected.

We had a fantastic presentation last week from IT expert and author Niel Nickolaisen. Niel shared his proven methods for reducing downtime and improving the alignment of IT resources to better support business goals. If you weren’t able to attend the live event, you can watch the recorded version here.

If you prefer a white paper format, Niel’s strategies and best practices have also been summarized in a brand-new 8-page white paper, “Reduce Downtime by 70% - Without Spending a Dime” which you can download here.

The Q&A session from the live webinar with Niel Nickolaisen and Michael Bilancieri of Marathon has been summarized below:

Q: Can you give some tips on how I can educate my branch offices about my business continuity plan?
Niel Nickolaisen, CIO: At Headwaters, Inc., we have 120 remote sites. We approached this from an SLA perspective. We translated how the SLAs affected the operations at our branch locations. Then we communicated it and got them to buy into the SLAs and the things we were doing and suggested that they followed our lead.

Q: How often should you update your disaster recovery plans?
Niel Nickolaisen, CIO: In our case at Headwaters, Inc., we have Sarbanes-Oxley regulatory requirements. We do an annual formal risk assessment both for our business and for IT. When we’re done with that assessment we update our disaster recovery plans, which are based on the risks. Our disaster plan is designed to mitigate or recover from the risks that we’ve identified.

Q: How does everRun work?
At a high-level, everRun takes your entire Windows environment and protects it as a whole. Most protect from within the OS but we protect from underneath the OS. We clone to a second system for redundancy in a synchronous fashion. A good way to understand how everRun works is to watch our product demos videos and flash demos available on our website.

Q: How does everRun fit into a virtual environment?
everRun allows the ability to create multiple workloads on a single server. Our technology is based on virtualization technology – we’re virtualizing two instances to appear as one. You can create multiple workloads and put them on the same server and protect them. It’s based on Citrix XenServer.

Q: Will this work in conjunction with SAN offhost backups using Vertias Netbackup and FlashSnap option?
We are agnostic to the storage. If you’re using back-up right from the SAN, that’s fine. You can also use a mirrored option, where we can mirror the entire system in a synchronous fashion. That allows you to have SAN on one side and NAS on the other, or direct-attached, or both. It’s your choice, which gives you greater flexibility. You can separate the servers as well between buildings. The other option is a single copy of storage, not mirrored and both systems can connect to that storage, but the SAN device will then have to protect the data.

Q: How can Marathon contribute to companies considering a move to SAP?
everRun can provide availability and fault tolerant protection to that SAP environment. If you’re considering a move to SAP, I would assume you have had some discussions about how to protect that—the SLA, the data, availability and disaster recovery. everRun can protect and provide disaster tolerance disaster recovery, and high availability for that application, as well as data protection. We don’t cause any changes to the application.

Q: Should Marathon be brought in as a consultant before SAP is contracted?
Sometimes it’s a good idea to have a joint discussion with vendors. A lot of times when you look at availability and redundancy or data replication, it’s doing things to the applications and data and can cause interaction issues. Sometimes the application has to be configured in a certain way, so you want to know up front how your high availability solution could affect the data and application. We can certainly do a call with any other software vendors to have that conversation up front.

Q: What version of Windows does everRun support?
everRun supports Windows Server 2003 32-bit and 64-bit and Windows Server 2008 64-bit.

Q: What kind of performance impact does the synchronous lock-step have on the system?
That varies by application, users, data, I/O, and other factors. In general, it can range from 10-20% on your application – we’ve seen less than that and more than that, depending on the system.

Q: Do you recommend WAN optimization to be used?
Our requirements are around bandwidth between the two systems if you want to separate the systems. WAN optimization tools don’t always help. It’s really a latency requirement to maintain good performance.

If you'd like to learn more about Niel's best practices for aligning business and IT resources, be sure to check out his new book, Stand Back and Deliver: Accelerating Business Agility.

Thanks again to those who joined us for last week’s webinar, "Windows Server 2008 High Availability: Technology Comparison." The on-demand recording of last week's webinar is now available to watch at your convenience (here).

We had a lot of good questions from our attendees during the Q&A portion of the webinar, which are summarized below.

Q: How do you determine when to use an HA solution vs. a DR solution?
When it comes to availability vs. recovery, the most important question to ask is what are your recovery time objectives (RTO)? What is the amount of time your application can afford to be down? If the applications have strict requirements, then you want an availability solution. Disaster recovery is data replication often times with a failover capability, not availability. For critical applications, this may not be sufficient.

Q: If I have an HA solution in place, do I still need a solution for backup?
Availability and backup are two different things. That question comes up a lot, along with the need for disaster recovery. Backup will never likely go away completely. You still need to backup your data to ensure recovery in the future should that be necessary.

Q: Is everRun available for Linux applications?
Yes. We can provide basic failover capabilities for Linux applications today.

Q: How does everRun differ from replication solutions?
everRun 2G is used for availability, both locally and for short-distance geographic separation as well. We have a replication and recovery solution as well that can be used for disaster recovery for long distances. You should determine what your objectives are: do I have to keep my applications up and running or do I just need to recover it if something fails? What’s the recovery time objective for each application? It’s up to your individual applications and what level of protection you need for each. Often times availability is a priority as downtime is not desirable, with DR also a requirement on top of that to ensure recovery in the event of a major outage.

Q: Can everRun be used for planned downtime (i.e. to keep one host running for end-users while the application on the other host is being upgraded)?
Yes, everRun can be used to help facilitate certain system updates to reduce interruptions and mitigate risk.

Q: Can it work between two virtual machines and on x64 based systems?
Yes, we support XenServer and 64-bit hardware and Windows Server environments.

Q: What is the performance impact of using everRun 2G?
That’s variable depending on your application. It can be anywhere from 3-15%. We’ve done some performance testing specifically on XenApp and Exchange. You can download those white papers here:
• Understanding and Characterizing Performance Implications for Running Exchange 2007 with everRun
• XenApp 5.0 High Availability Performance

Q: Does Marathon offer backup solutions for everRun users?
We have methods to backup your systems and we’re working improving on our current offerings to make them quicker, easier and more granular.

Q: Can everRun work with dissimilar hardware? Can everRun work with more than two servers?
From a server standpoint, you just need similar processors; storage does not need to be similar. You can have SAN on one side and NAS on the other or any other combination. On the second question, yes, everRun will work with more than two servers. You can build a pool of servers and protect within that pool.

Q: Does everRun have backward compatibility with older OS?
Yes. It will work with Windows Server 2003, and also Windows Server 2008.

Q: Can everRun run on the Foundation Server Edition of Windows 2008?
It does not. everRun supports the full implementation of Windows Server 2008. everRun runs underneath Windows, it does not install into Windows.

Q: How does everRun handle data stored on NAS?
Storage is transparent to everRun. We look at storage as just a LUN.

Q: What is difference between everRun HA and everRun 2G in Windos Server 2003?
The differences are the ability to create multiple workloads. HA can protect one workload. everRun 2G can protect multiple workloads. There is also a new and improved graphical interface with better reporting and management capabilities.

Q: Does everRun work with XenServer 5.5?
Yes, everRun works with XenServer 5.5.

Q: Are there any changes in WS 2008 & WS 2008 R2 in the way that HA improves?
Yes. You can find an overview of those changes directly from David Hanna of Microsoft in our recent webinar and white paper “The Top 10 Reasons to Upgrade to Windows Server 2008.” You can also read the Q&A with Microsoft from that webinar here.

Q: Is everRun 2G available for Microsoft Hyper-v?
We will provide support for Hyper-v in a future release.

Q: With applications using various DNS names, how does this solution integrate with DNS changes? (failover to remote office for true DR-different IP/network)
everRun availability solutions pairs systems within the same subnet of vLAN, eliminating the need to make any DNS changes.

Q: Question is tied to what permissions are needed to do a recovery. For recovery in active Directory most items need to replicate around that there was a change and we do not want to hand out Admin control over the domain(separation of access)
everRun is designed to not require any changes to Active Directory during or after a failure or recovery.

Thanks again to those who joined us for last week’s webinar, “How to Get at Least 2x Greater Cost Savings from Server Virtualization.” An on-demand recording is available to watch at your convenience (just click the link.)

We had a lot of good questions from our attendees during the Q&A portion of the webinar, which are summarized below.

How does everRun synchronize and how often?
everRun synchronizes as the data is written to the virtual machine. It’s not done on a time stamp. It is synchronously written to both physical hosts. We do a bit check to make sure both sides are written prior to responding back to the application, stating that it has been written, so that the data is always in a constant state and there is no data loss.

If I already have XenServer installed, can I install everRun on top of it, or do I need to reinstall XenServer?
everRun can be installed into existing XenServer environment. We do have resource pool requirements, so as long as you in a resource pool or can join yourself to a resource pool with a second server, or multiple servers for multiple host pools, we can be installed into an existing XenServer environment.

How does it support local storage? If the server that is hosting the storage goes down, what happens?
We mirror the virtual machine across two servers, so there are two copies of your virtual machine. Where we sit in dom0 (Xen domain zero), we have filter drivers sensing that type of situation. When using Level 2 protection with everRun, if you lose local storage, we leverage the copy of the info on the second server for zero downtime. If you were to lose the entire server, it would failover to the other side and start in Windows services. In Level 3, the same procedure applies to local storage. If you were to lose the entire server with Level 3, everRun allows it to simply continue functioning because we are running active-active.

Have you used this with a building automation system, such as Andover Controls Continuum which runs on a SQL Server?
We have a very large building automation practice here at Marathon and have worked with all flavors of SQL server. We have been working for years with building automation and security companies such as Johnson Controls, Tyco, Andover Controls, Siemens and many others. As long as the building system runs in Windows Server 2003 or 2008, we can provide availability for it with no custom scripts or custom coding.

What's the overhead with regards to CPU, memory, disk space of the host?
Generally in the 3-5% range. We’ve done some performance testing on XenApp and Exchange. You can download the results papers here:
• Understanding and Characterizing Performance Implications for Running Exchange 2007 with everRun
• XenApp 5.0 High Availability Performance

Can everRun be used with homegrown or custom applications?
Yes. everRun is completely transparent to the application and can support any and all Windows applications without any modifications, customizations, or scripting.

Can everRun protect a workload that is physical on one side and virtual on the other?
We do not support P2V today, but we have an ongoing research project on this topic. You can contact your sales rep for more info.

What is the maximum number of workloads that can be run using everRun?
The best way to answer this is to look at your virtualization planning assessment, including power capacity planning and hardware capacity planning. If you can support 10 virtual machines on a server, then you can support 10 virtual machines protected by everRun on that server with no problem. We also require a similar machine as the secondary server running on the same resource pool. It really comes down to how much your hardware capacity can handle.

How to take care of software corruption?
Because we are a synchronously written high availability solution, if there is software corruption on one side, we are going to replicate it to the other side. We sit at an asynchronous block-level filter driver location, so we have no ties to the software. So if it corrupts, it will corrupt on both sides.

Are you currently developing for Exchange 2010?
Yes, everRun will support Exchange 2010.

Does everRun support Small Business Server?
Yes we do. We’ve tested and qualified it for 32-bit and 64-bit versions of Windows Server 2003 Small Business Server Edition.

Does everRun replicate all server data including application data like a SQL database?
Yes. We replicate synchronously at a block level. We sit inside dom0. We then send the info block level to the other side. We do a block check and then we check our bit map to make sure the blocks are synchronously written on ongoing basis.

Can everRun be installed on top of XenServer 5.5 ?
Yes. We will support 5.5 in our next release scheduled for September.

Can we achieve DR?
Marathon offers a couple of options for disaster recovery (DR). Our SplitSite product can be used for metropolitan/campus DR, up to 150 miles apart, depending on your network conditions. We also offer everRun DR, for DR sites that are more than 150 miles apart.

Is the disk mirroring full copy or delta?
Upon initial protection we do a full copy. After you have a failure, such as an iSCSI card failure, we will do a delta copy back over to what’s missing. If you lose the entire RAID set, then we will need to do a full copy again.

Is the price of implementation based on the server capacity?
You need to purchase a license for each server in the pool. In terms of virtual machines (VMs), the license covers as many VMs as you can support in a box.

Our July 30th webinar “Top 10 Reasons to Upgrade to Windows Server 2008 Now” was very well attended, and as expected, generated a lot of good questions. So many questions, in fact, that we weren’t able to answer them all during the live Q&A portion of the webinar.

For your convenience, we’ve captured all of the questions below. Answers have been provided by our speakers, David Hanna, Infrastructure Architect at Microsoft, and Michael Bilancieri, Senior Director of Products at Marathon. The questions are grouped by topic, starting with Windows Server related questions and then Marathon everRun related questions following after.

How seamless is the migration from Windows Server 2003 to 2008?
It really depends on the workload. Active Directory upgrade is similar to the 2000 to 2003 upgrade, and should not be disruptive. Cluster migrations require a rebuild of the cluster. For IIS, many applications can be migrated easily. It’s best to look on Microsoft.com for migration info that is specific to your workload. Simply introducing a Windows Server 2008 server into a 2003 environment should be seamless.

Going from Windows Server 2003 to 2008, do you recommend upgrading or re-installing the operating system?
Microsoft supports an upgrade of the OS only – no applications. Most customers however, choose to reinstall with Windows Server.

What are the hardware requirements for this Windows Server 2008?
Minimum is a 1ghz processor, 512mb of RAM, and 20GB of disk space. Details can be found here: http://www.microsoft.com/windowsserver2008/en/us/system-requirements.aspx

Do you have an actual laboratory so that I can practice Windows Server 2008?
You can find the TechNet Virtual Labs here: http://technet.microsoft.com/en-us/virtuallabs/bb512925.aspx

Any difficulties adding a Windows 2008 Server into a 2003 domain? Anything to watch out for?
Adding Windows Server 2008 Member servers to the domain should not be an issue. There are no special things to watch out for, until you start adding Domain controllers. Note that if you add a 2008 member server, and do not extend the schema, some things will be unavailable, like the enhanced DFS capabilities in 2008.

Where can I get a copy of the Windows Server 2008 trial version?
You can obtain the trial version here: http://www.microsoft.com/windowsserver2008/en/us/try-it.aspx. Starting August 20th, you will be able to get R2 in the same location.

Can I do in-place upgrade AD server 2003R2 to Server 2008 without any problem? Also, can I do that same thing with Exchange 2007 server on SRV2003R2?
Microsoft only supports the upgrade of the Operating System from 2003 to 2008. We do not support the upgrade of Windows Server 2003 with applications, so the Exchange 2007 upgrade would not be supported.

Is it possible to use the same imaging deployment method for Windows 2008 physical and virtual machines (in VMware) for consistent builds?
It is possible to use traditional imaging methods for physical and virtual, however in the virtual environment, most customers tend to use template Virtual Hard disks to deploy systems, as it is faster and more flexible than imaging.

What is the difference between GPO and NAP?
Group policy is a part of Active Directory that allows for management of users and computers. NAP, or network access protection provides endpoint health checking for network clients. This integrates with network components to restrict or allow network access. Client NAP configurations can be controlled by GPO, and some GPO settings can be enforced by NAP.

Does NAP work for VPN connections as well?
Yes. It is integrated with Microsoft VPN as well as some partner solutions.

Does XP pro and 2008 Server talk well together? What’s a better path, upgrade your clients to Win7 then servers to 2008? Or vice versa?
XP will work in a 2008 domain environment, but it won’t be able to take advantage of all of the features of 2008. Vista is designed to complement 2008, and Windows 7 works best with 2008 R2 (or 2008). I would recommend deploying Windows Server 2008 for workloads that will gain the most benefit – this will allow you take advantage of it immediately. Then follow with Windows 7 when you are ready.

Do terminal servers have central management to manage users and applications?
There are a number of tools to centrally manage the environment. R2 adds a connection broker component that will publish apps from multiple servers. However, apps still need to be published on each server, and permissions need to be set that way as well. Citrix provides some great centralized mgmt tools that enhance the native tools.

Will 2008 support XP clients?
Yes. 2008 will support XP for many things including Terminal Services, with RDP 6.1 client, NAP, with XP Sp3, Group policy preferences and many other features. Windows Vista and Windows 7 however, are able to take advantage of more features.

I have two Windows 2008 servers that are going to be setup as a cluster for Exchange 2007. Is there a document for setting up the “heartbeat” connection between the two servers?
There are many documents on technet that will help. When you build the cluster, the validation wizard will check the configuration of the heartbeat network to make sure its configured appropriately. Typically, a 2 node cluster will use a cross-over cable, although a non-routed VLAN on a switch also works. Some docs:

Step-by-step guide for basic 2-node cluster: http://technet.microsoft.com/en-us/library/cc731844(WS.10).aspx
Validating an Exchange 2007 Cluster: http://technet.microsoft.com/en-us/library/bb676379.aspx

Is Server 2008 with Exchange supported on VMware?
Exchange Server 2007 SP1 on Windows 2008 is supported – see here for details: http://www.windowsservercatalog.com/svvp.aspx?svvppage=svvp.htm

Is it possible to run a 2008 DC with 2003 DCs without any sort of hacks or work-arounds?
Yes – it is possible. You’ll need to extend the AD Schema and install a 2008 member server, then promote it to a DC. There are some documents here: https://blogs.msdn.com/canberrapfe/archive/2009/04/08/adding-a-2008-domain-controller-to-your-2003-forest.aspx

Regarding the NAP, once a client is quarantined, is there a policy or rule that the admin must create to get the client healthy? Meaning, is it automatic or does the client sit there until someone checks the quarantined clients and fixes the issues?
NAP can be configured to auto-remediate certain things – turning firewall on, turning on autoupdate, etc. For AV, or patches, users can be directed to a web page with simple instructions or links to update the client.

Has load balancing improved with 2008 and TS?
It has been made simpler. Many customers found NLB to be complicated for what was needed on Terminal Services. TS on 2008 uses DNS round robin for initial connection with the TS Farm, then load balancing across nodes is handled by using RDP session load balancing.

How many CALs are included in the bundle of Windows Server 2008?
There are different bundles with 5, 10, or 25 CALS. http://www.microsoft.com/windowsserver2008/en/us/pricing.aspx

How many machines can run on a single user MS Windows Server 2008, because we want to move to VMware soon.
Microsoft supports up to 192 VMs on Windows Server 2008, and 384 on Windows Server 2008 R2. Typically numbers will not be anywhere near this, as other system resources will bottleneck. Details can be found here: http://www.microsoft.com/windowsserver2008/en/us/hyperv-faq.aspx#HyperVWindowsServer2008Specific

Is MS Windows Server 2008 VMware built-in?
Microsoft’s virtualization solution, Hyper-V, is built in to Windows Server 2008 and R2.

How would Hyper-V handle the VMware over committing resources, for example, is ESX server only have 8GB RAM but it can assign 16GB RAM to the VMs because it holds the memory and only releases it when it is required. The main reason for Exchange on a ESX box is not a good idea.
Hyper-V does not support over-commit of memory resources. To assign 8gb of RAM to a VM, you must have 8gb available. This improves performance and security.

What happens when a file which has been transferred/shared to a branch using Branch Cache is opened in the main office? Will the branch be informed about this and vice versa?
When clients use branch cache, each file is referenced by a hash. When a client tries to retrieve a file from the central office, it checks the hash of the file, then compares it to what is in the local cache. If the file has changed, then the hash would have changed, and the client would retrieve the updated version. The branch is not informed if the central copy is opened, only if it is changed, through the hash mechanism.

What is the maximum supported DFS server in 2008? In 2003 I think it is less than 70GB and that was not enough for me.
The File Replication Service in Windows Server 2003 had trouble with replication when data sizes got too big. Windows Server 2008 uses DFS-R (Distributed File System Replication) for replication – this uses an algorithm call Remote Differential Compression, which compresses files, and replicates only changes. This makes replication more efficient, an able to support large volumes of data. The limits that existed in 2003 for data size are either removed, or raised greatly.

What is the standard vs. reduced footprint for Windows 2008?
Processor requirements for Server Core and full Windows Server 2008 are the same. Minimum memory recommendations of 512mb are also the same. While the system requirements on Microsoft.com don’t list separate requirements for Server Core, it typically requires less disk space than a full installation. Additionally, Server Core has fewer roles to install (only 9), fewer services running, and has no GUI.

Are there any plans to integrate snapshot technology within Hyper-V?
Hyper-V already supports snapshots at two levels. First, it supports snapshots of the Virtual Machine itself, through use of memory copies and differential disks. The other snapshot capability is a snapshot backup, performed by the host Hyper-V system, using Volume Shadowcopy Services to back up the running VMs.

When will Hyper-V R2 be released?
Windows Server 2008 R2 and Hyper-V R2 released to manufacturing on July 22nd. General Availability will be in October. Volume license customers should have access to the code on August 19th. More details are available here: http://blogs.technet.com/windowsserver/archive/2009/07/22/when-to-expect-windows-server-2008-r2-rtm.aspx

Can everRun protect a workload that is physical on one side and virtual on the other?
everRun does not install INTO a Windows system, so it isn’t able to protect a ‘physical’ system in this sense. Many of our customers choose to keep some of their applications isolated to a physical server with no other applications or VMs on that host while protecting them with everRun. This is done by creating a single Windows environment within the everRun environment. Although the capability is there to create multiple, a single is the desired approach.

How does everRun handle data stored on NAS?
everRun can use any product data that resides on any type of storage. everRun sees the storage repository as a disk volume and can mirror between any two.

How many licenses for the operating system do I need for this solution? Do I need two licenses for the application (i.e. Exchange) as well?
Typically two licenses of Windows are required, however the Enterprise edition provides benefits when running in virtual environments. Please check with Microsoft on this and with your application vendors as all vendors have different licensing terms for redundant/high availability systems.

How well does everRun work with dissimilar hardware (i.e. at the DR site using older servers)?
There are some requirements for similar server components. If two supported servers are utilized and one happens to have a slower processor, the application may run at the slower speed, depending on the level of protection chosen within everRun.

Does everRun replicate all server data including application data like SQL databases?
Yes. The entire operating environment and all disks, including the OS, application, and application data are mirrored.

Is everRun effective for small companies? For example, an Exchange environment for less than 200 users?
Absolutely. Many of our customers are smaller to mid-sized businesses who require an availability solution that is simple, effective, and doesn’t require SAN storage or dedicated IT staff to manage.

Does everRun support MS Small Business Server?
Yes. Our everRun solution will work with any version of Windows Server, 64-bit or 32-bit. We work for small scale solutions all the way up to enterprises.

Will everRun support Exchange 2010 DAG location geographically?
We are still researching Exchange 2010 capabilities and how they can best be supported by everRun. At this time we are not yet clear on how DAG will or can be supported.

How are system upgrades handled in the everRun environment?
A single upgrade is performed on the single exposed Windows environment. Both of the redundant systems will be updated automatically by everRun. everRun also offers mechanisms to reduce the risk and associated downtime of system upgrades.

How does the actual SQL server app run in the everRun environment?
Exactly the same as it does in a non-everRun environment. everRun sits below the Windows environment therefore there are no application changes required.

The everRun software sounds great, but it requires two physical servers. Any hope of moving forward to do the same work within a VMware or Hyper-V environment?
Today everRun supports virtualized environments running on Citrix XenServer. We announced a joint development agreement with Microsoft back in early 2009 to provide everRun Fault Tolerance within a future version of Windows/Hyper-V.

How is everRun migrated with Windows 2008 hypervisor?
everRun will support a future Windows/Hyper-V release as part of the joint development effort between Microsoft and Marathon.

What system resources are used by everRun?
A small (varies a bit by the application that is running) bit of CPU and memory overhead is consumed by everRun.
 

If you’ve been thinking about upgrading to Windows Server 2008, be sure to attend our July 30th webinar featuring guest speaker David Hanna, Information Architect at Microsoft. David will review the new Web tools, virtualization technologies, security enhancements, and management utilities available in Windows Server 2008. You’ll also have a chance to ask David any specific questions you have about Windows Server 2008 during the live Q&A portion of the webcast.

In preparation for the webinar, we asked David to answer a few of the common questions that we have been hearing from our customers in recent months.

Q: One of the biggest concerns we hear from our customers and partners is that in this current economy, IT departments are being asked to do a lot more with less people. How can Windows Server 2008 help with this issue?

Across all of my customers, everyone is talking about cutting costs, and getting more out of their current investments. When we start digging into the features of Windows Server 2008, customers are finding tremendous opportunity to optimize their environments. A few of the major areas of cost savings I’m seeing are:

• Reduced deployment time and costs with Windows Deployment Services
• Reduced management cost and effort with PowerShell and Server Manager
• Hardware and Workload Consolidation with Hyper-V
• Licensing consolidation with Enterprise and Datacenter models for virtual environments.

Q: What about the challenge of managing remote and branch office locations?

Branch offices have consistently been a challenge to manage, primarily due to lack of on-site staff. Windows Server 2008 brings some major new components to the picture that will greatly ease branch office management. These features include the Read-Only Domain controller, which makes the remote DC secure, and replaceable, Distributed File System, Windows Remote Management, Server Core (lower surface attack area), and improved Terminal Services for application delivery.

Q: A lot of our customers work in “always-on” industries like manufacturing, healthcare and broadcast media, where server downtime can be very disruptive to their business. How does Windows Server 2008 support these demanding environments?

Windows Server has always addressed high availability with Clustering Services. Windows Server 2008 has brought some huge enhancements to the Cluster Service that will reduce the complexity of clustering, while increasing availability. Failover Clustering in Server 2008 has a new validation wizard that will validate hardware and software configurations, resulting in easier, more reliable cluster deployments. The reliance on a quorum drive has also been removed, so there is no longer a single point of failure in the cluster. Also, Failover Clustering has been enhanced to support multi-site clusters to support organizations that need site-to-site failover. And, as always, when organizations need to take availability to the next level, Microsoft continues to work with partners like Marathon to extend the native capabilities of Windows Server.

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During the webinar, Michael Bilancieri, Sr. Director of Products for Marathon, will discuss how to extend the high availability features of Windows Server 2008 to fault tolerant protection with Marathon’s everRun software and how organizations can now confidently migrate mission critical applications from Unix or proprietary platforms to realize big cost savings.

Registrations for this webinar are limited and we are expecting a large turnout, so be sure to save your spot by registering today.

This afternoon I was fortunate enough to lead the “Breaking Through the Confusion About Disaster Recovery and High Availability” Webinar. I would like to thank everyone that attended and give a special thanks to Alex Jarret from the Technology Executives Club for hosting the event.

Unfortunately there was a minor error towards the end and participants did not have the opportunity to send me their questions, except for one individual who asked if I could provide them with the presentation. In response, I’ve made the presentation available in PDF format which can be downloaded here.

If anyone that attended the Webinar had any questions they haven’t yet had a chance to ask or new questions arise while reviewing the presentation, please feel free to email them to me directly at MBilancieri[at]marathontechnologies.com and I will do my best to answer them.

Virtually every company we talk to needs both disaster recovery solutions to recover their systems and data after a major disruption, and high availability to keep key applications always available. In my discussions with companies considering our everRun software, I’ve heard a lot of them say that they are confused by many vendors’ claims and counter-claims for DR and HA. One of the biggest sources of confusion is that some vendors with solid products for disaster recovery are trying to pass off their DR solutions as reliable HA solutions. If the feedback I’m getting is any indication, these DR solutions posing as HA solutions just don’t work.

It’s not hard to see why a DR solution doesn’t make a good HA solution. With a product that is good at DR, in most cases getting the data across to the other location is pretty straightforward. But when you try to use the same solution to get both the application and the data across to use it for HA, well that’s where it breaks down. Let’s look at why.

A good DR product is usually fairly easy to set up for data replication to another site. But setting up the same product to restart the whole thing, application and data, when a failover occurs is complex and prone to errors. To set it up, you have to script all the pieces to make it happen – fault detection, client redirection to the DR site, application reset, and the list goes on. No wonder we so often hear that scripted-DR-for-HA doesn’t work consistently – there are too many moving parts that have to managed and monitored. In addition, no matter how minor a failure is, failover to the remote site is required. Not every failure you face is a disaster; therefore each failure should not be treated as one. Based on these horror stories, we thought it was a good idea to put together this webinar, Breaking Through the Confusion about DR and HA. I hope to help you better understand when, how, and why DR is the best fit to meet your requirements, when to use an HA solution and how to combine the two for optimal protection.

Interested? You can register here.

Following last week’s discussion, event attendees had additional questions that we didn’t get to answer even though we went ten minutes over. We wanted to continue the discussion here on our blog so we figured we would post the continuation of questions and answers for everyone to see. As we mentioned before, if you would like to view the presentation delivered last week by John Humphrey’s (IDC), Simon Crosby (Citrix) and Jerry Melnick (Marathon), download the presentation here.

Are there any performance limitations with everRun VM?

everRun VM supports any guest environment created by XenServer, including multi-CPU VM’s.

Effect of losing inter-server link?

As a best practice we recommend two Availability Links for redundancy. If one should be lost, we will continue to operate unaffected using the remaining one. If both are lost we will take action to prevent complete loss of the VM or SplitBrain.

How far apart can the two machines be – i.e. is there a propagation delay issue?

Host separation is a factor of network latency, which must be <10ms round trip. Current deployments have exceeded 100 miles.

In case of a disk failure, does everRun rebuild the disk from the good physical host to the bad one?

Correct. Recovery of storage is handled as a background task so as not to require downtime or otherwise impact the running VM and application.

When will level 3 of everRun VM be available?

Level-3, System-Level fault tolerance is scheduled for later this year.

What requirements are associated with the everRun Level 3 Protection? (Bandwidth, latency, etc.)

Network and configuration requirements are the same for level-2 and level-3 protection.

Is StorServer a similar or competitive product to everRun?

StorServer is a backup appliance, not a fault-tolerant availability solution, and addresses very different requirements. It would be more complimentary then competitive.

What virtual machines (VMware, Parallel, etc) are supported by Marathon?

Currently only Citrix XenServer, however future plans are to expand upon this.

Are there certain applications that are not suited for everRun, such as I/O or compute intensive apps? Home does DR configurations affect performance?

This is very dependent on the configuration of the server, the VM, the storage and all other components. Appropriate best practices should be followed to ensure optimal performance for all applications.

Can Marathon support physical to vm HA? Does Marathon’s product fully support FC/iSCSI SAN shared storage between protected physical and/or vm pairs? Does Marathon product support local site HA server pair with a third node at a remote site in the event of site failure? Does Marathon product have latency limitations?

Marathon offers solutions for physical and virtual servers. These solutions utilize the same proven fault tolerant technologies however are independent of each other. everRun VM supports any type of storage that is supported by XenServer. Fault tolerance is configured using two VM’s. However we will soon be releasing an asynchronous solution that will allow a third replicated system at a local or remote site. Because everRun VM is a synchronous solution there is a latency requirement of 10ms round-trip between hosts. Our asynchronous solution will not have any latency requirements.

What is the pricing of everRun VM?

everRun VM lists at $4500 when bundled with XenServer Enterprise, and $2000 if you already have XenServer.

Thanks for all of your interest and questions.

There was a great turn out for the joint Citrix and Marathon Webinar today, The “Best of VMWorld Approach” to Virtualization and Availability. Thanks to everyone for attending. If you missed it or want more information visit here to download the presentation.

There were a lot of great questions for Simon Crosby and Jerry Melnick, which we have captured below. If anyone has any additional questions, feel free to leave a comment here on the blog or contact us directly.

Simon: Do you need 64-bit hardware to try out the express edition?

All modern server hardware is 64 bit enabled. Xen uses all of the modern features of Intel VT or ANDV to perform hardware virtualization of Windows; so the answer is yes but if you have a modern server you’re in good shape.

Jerry: How does everRun VM’s second level of availability differ from VMware HA?

One of the key pieces is that we compute through the failures of any I/O fault or failure, and then automatically redirect I/O to the device that survives it. In VMware HA, the failure of an I/O device isn’t necessarily detected or managed it’s just host failure. We are managing virtual machine failures in related I/O devices.

The second piece is that we’re doing active validation of all the devices so that we know at all times if all the resources are available and that they can actually be utilized in the case of recovery. If you don’t have active validation, such as with VMware HA, you can failover your VM and get to the other side but you may find that the device which handles the disk isn’t actually operational because of either a failure in the hardware or some kind of problem administratively with how you configured it.

Simon: Is there an extra cost associated with XenCenter?

No, it’s just a pre-feature of the product. Our architecture does not require something like virtual center because every server in the resource pool redundantly has every piece of information for the entire resource pool. Should any server fail, we automatically elect a pool leader from the remaining servers and all mainstream information is highly available as a result.

XenCenter itself is a perfect thin client UI which interfaces with as many resource pools as you want to run, but it is literally a thin UI – it’s stateless, and all of the state related to managing the infrastructure is in the infrastructure itself, which allows us to really scale this architecture.

Jerry: In the demonstration you gave, are users hitting both hosts in the exchange application being protected?

In the level 3 fault tolerance configuration we are running both hosts redundantly which is what you need to do for full system-level fault tolerance. In level 2 the amount of resource being utilized is less because you’re actually only running a virtual machine on one of the hosts, but you’re running I/O on both of the hosts. In level one you’re running at the next level down, with only a single VM allocated and no preallocation of the secondary side, with all I/O processing on just that one side. There is no active redundancy. That’s why we provide the different levels; so that you can choose which virtual machines really need to use that resource and have that ability, and which ones you want to make some trade-offs of availability versus resource utilization.

Simon: What does it mean to have a 64-bit hypervisor and why is that better?

If you have a 64-bit hypervisor then you can host both 32 and 64-bit guests and you don’t have any issues really to address space conversion problems. It’s a cleaner architecture, the memory architecture scales massively up to four terabytes (not that you can buy a server that has four terabytes of thin slots), but it allows us to massively scale the memory and CPU of the system. We support up to 32 physical CPUs and a box as a result, and we have an architecture that is going to scale superbly for us.

Jerry: Do you need a dedicated LAN to run everRun VM?

The only dedicated LAN we use, and can actually be shared because of the flexibility of XenServer itself, is what we call the availability link which is part of our best practices. Otherwise it’s all a standard LAN configuration that you would have in the XenServer pool.

Jerry: Are there certain applications that are not suited for everRun?

Our technology is completely transparent – relative to the application itself. Any windows application that you run on a Windows VM can be run by our technology.

Jerry: Is it possible to combine XenMotion with everRun VM?

As part of our capability, the ability of motion of VM from one host to the next is extremely integral to it. You get the capabilities to provide recovery from failures as well as to be able to have planned downtime and migrate your VMs when you want to do a repair. It’s an integral part of the product and we use XenMotion as the backbone of it. One difference with everRun VM is that we allow this motion capability without the need for a shared-LUN, or SAN, storage subsystem.

Simon: How would a current ESX 3.x customer migrate to a Xen environment and why should they do that?

There are free tools available to do this which can be downloaded off our forums and indeed Microsoft has similar free tools available. Here’s why you would do it: we guarantee that Citrix XenServer VMs are literally compatible with Microsoft Hyper-V. They’re also compatible with every other Xen implementation. What I see emerging is essentially two camps: A camp in which there is an open architecture (Microsoft storage architecture is very similar to XenServer, it’s also an open architecture) where you’ll have a bunch of virtual infrastructures out there from different vendors all of which are interoperable; and then a camp where there’s VMware.

The reason to move to XenServer is that we are fundamentally focused on a rich ecosystem of value added providers. We are diametrically opposed to an architecture which presumes that everything comes from one vendor, and where the entire architecture is dictated to you. The moment you invest in an architecture which is one size fits all (cost aside) you will find that it has limitations.

I am starting to see that the one size fits all architecture, which has done VMware a great favor for its first 10-15% of the market, is starting to show signs of age as we look at new use cases. For example, for desktop virtualization or for high availability, you can’t do this with that architecture and its no surprise then that at VMWorld the awards for innovation go to open architecture and best of breed vendors – Marathon at VMWorld winning the award for fault tolerance. We are dedicated to an open architecture and best of breed.

Jerry: Is Marathon planning to protect Linux based VMs in the near future?

Our road map will extend over the next year to protect all the hosts that are supported by XenServer.

Simon: Can you give a rough idea of the performance overhead of a virtual server vs. a real server?

It’s highly dependent on the workload. Typically we see between .5% and 2% overhead even for very I/O intensive workloads. For Windows it’s notionally higher. The great thing about this is that we are writing the hardware code; unlike my friends at VMware who are still tied to software implementation of virtualization in which they have to patch the binary of a running guest operating system. We ride the hardware improvement curve of Intel and AMD. What we’ve seen there is roughly a three-fold performance increase per year. Typical overheard for virtualizing Windows guests is around 3-5%. The most intensive workload I have ever seen is in fact Windows Terminal Services or our own Citrix Presentation Server where we currently stand at about 8% overhead.

Jerry: Does everRun VM support shared storage?

Yes. We actually support any capability in storage. Whatever kind of LUN that you can present to XenServer and carve up into a storage repository or a VHD, we will support that. If it’s a local disk, low-end RAID storage or just a bunch of disks we will support that, as well as high-end SAN storage. The advantage of the product is that we will support local storage for very low-end small environments.

Jerry: How far can the servers be separated?

It is not a matter of actual distance but rather a matter of network connectivity between the two hosts. We have systems currently deployed with separation of greater than 100 miles.

Last week our own Jerry Melnick sat down alongside Chris Wolf, an analyst for the Burton Group, and Simon Crosby, CTO of XenSource, for a Webinar to discuss the new technology bringing fault tolerant-class availability to virtual environments. Overall feedback was positive, with comments that the session was informative and thought provoking. For those of you that may have missed it (or those that just can’t get enough) we posted a recording of it here at the bottom of the page.

Listen, Share, Enjoy!

Presenters:
Chris Wolf, Analyst - Burton Group
Simon Crosby, CTO – XenSource
Jerry Melnick, CTO – Marathon Technologies

At VMworld 2007, Marathon won Best of VMworld – New Technology for bringing fault tolerant-class availability to virtual environments for the first time. Attend this webinar to learn from Chris Wolf of Burton Group how to get the most out of your virtual environment. Simon Crosby of XenSource will explain how XenEnterprise v4 simplifies virtualized DR and availability. And Jerry Melnick of Marathon will demonstrate how you will be soon able to protect business critical applications with fault tolerant virtual machines.

November 1st, 2007 - 11:30AM-12:30PM Eastern Daylight Time (GMT -04:00, New York)

Register for this Webinar

Last week we had the opportunity to speak with the folks at Tech Target and discuss how large and small companies are keeping their Windows Server based applications up and running without the hassle of clustering. Michael Bilancieri, our Director of Products, took time to address the market confusion and noise around the topic of availability.

For example he uses the illustration below to describe various levels of availability. As noted before, there are many misconceptions regarding “availability” so we’ve created this diagram to illustrate the different layers and help explain where everRun fits in the mix.

We encourage you to listen to the webcast which can be found here and send us any questions or comments you may have.