Sites XenDesktop - Scale Up or Out

7:26 PM
Sites XenDesktop - Scale Up or Out -

How many jobs can one XenDesktop 5.x site support? I get asked this question a lot. Tests have been done showing that the site can support 10,000, 20,000 or more workstations. But my question is whether this is really important. After a number, I was still wondering if putting that many jobs in one site is really a good idea. It all comes down to what level of risk you are willing to take. Let me go through what I mean

  • Home Risk: At the basic level, we have a host hypervisor (XenServer, Hyper-V or vSphere). Depending on the hardware and user workload, I'll be running somewhere between 50-100 virtual Windows 7 desktops on each host. If the host has a catastrophic failure, these desktops offline. Users will try to reconnect and they will be sent to other hosts. That's why we recommend a minimum N + 1. If you lose a host, you must have at least one extra to take over. If you lose a host, you can expect most of these users to try to reconnect immediately. Try to support easy connections 50-100
  • Pool / Cluster risk :. A higher level that the host is a host group in a pool or cluster. You'll probably around 800 workstations in a pool / cluster if we assume that you have 10 hosts in a cluster. What happens if we lose the cluster? Depending on the type of failure, you will have one of the following:
    • Connection Failed: If you have a failure where the controller Pool / cluster fails, you will not be able to launch new workstations, but currently active users will not be aware of all the issues
    • default pool / Cluster :. If you lose a whole / cluster pool, you must find a place for the 800 desktop users. Again, if you have N + 1 fault tolerance, you probably have a spare capacity throughout your environment. You should also make sure that your infrastructure can support 800 users attempting to connect simultaneously. This is still not that big of a connection storm
  • Risk XenDesktop site :. A higher level than the pool / cluster is a XenDesktop site. A site may contain 20,000 or more workstations. But what happens if we lose an entire site for some reason? This is rare, but can happen. Remember, once the users are connected, they can work unless their host fails. But if the site is a catastrophic problem during logon storm, we should have a + 1 fault tolerant solution of N, which means that we must find a place in our environment to support 20,000 posts additional work will be used for fault tolerance.

Hope that all makes sense so far. But 20,000 jobs is a lot. The amount of material necessary to support N + 1 solution for 20,000 workstations is a lot. What if we create four XenDesktop site with only 5,000 workstations? I always support 20,000 jobs, but because they are in different sites of XenDesktop, the overall risk is greatly reduced. If something happens to one site, it should not affect the other three sites. These 5,000 users failed site can be balanced through other sites or 5 e site that is used in the case of a major failure (active / passive deployment).

A comment I always hear with this approach is that now I have to manage XenDesktop 4 or 5 sites. You must manage several sites, but you're not really manage additional components. With the process and the appropriate scripts, many of these management tasks can be simplified.

Just because XenDesktop 5.x can support tens of thousands of jobs, you need to determine whether this is the best approach for your business.

Daniel - Lead Architect
XenDesktop Design Handbook

Previous
Next Post »
0 Komentar