AP08 – Virtualizing Citrix XenApp Application Server Session
Delivered by Michel Bond & Holger Temme, who are Global Solution Consultants at VMware.
Now that 92% or customers feel confident that mission-critical apps run well on VMware, these have included some of the following in production:
- SQL Server
- Oracle
- IBM DB2
- SAP
So there is no reason not to virtualise Citrix XenApp servers. It is very easy to virtualise everything aside from the application servers in a typical Citrix ecosystem, such as:
- License Server
- Data Collectors
- Web Interface
- Datastore Servers
What makes XenApp Servers possible virtualisation candidatres:
Most XenApp deployments still on 32bit due to compatability and vendor support, which can cause application silos to be created. This in turn can result in under-utilised servers. On top of this the sweet spot for number of processors is dual core. There are currently far too many issues around 64 bit Operating Systems and the apps running on them for most people to use x64 in a terminal Services environment. So all these factors can create under utilised XenApp servers.
Advantages:
- x64 & x86 XenApp Virtual Machines can co-exist in the same VMware cluster which makes management a lot easier
- Template provisioning makes creating more XenApp servers a breeze
- Hardware refresh means that you don’t end up with even more under utilised servers when new processor families are introduced etc
- Next generation of Hardware Assist will give a 20% increase in XenApp server performance
Considerations:
- Manage user expectations when discussing consolidation ratios – use scale out not scale up, increase the number of XenApp servers
- Test real-life workloads, not just taking benchmarks on the internet as gospel as they only usually discuss Microsoft Office
- Do not use P2V as it can cause more problems than it solves – Registry bloats and can have HAL issues so avoid at all costs
- Use AMD’s RVI or Intel’s EPT
- Using 2 vCPU template can be the sweet spot, but make sure you test
- 1:5 Consolidation ratio is usually achievable, don’t over-reach
All in all a good session if not really technical enough for my liking.
