VMworld 2016 Roundup: Day 5
Successfully Virtualize and Operate Your Microsoft Skype for Business Infrastructure on the VMware vSphere Platform [VIRT7620]
I was interested in attending this session on Skype for Business, delivered by Adam Ball, Rakesh Gajwani, and Hemal Doshi as this seems to be a hot topic as of late. First, what is Skype for Business? Skype for Business (SfB) if a real-time communications platform. It requires negligible latency, as “real-time” is synonymous with “live”, as far as end-users are concerned.
If it’s not tuned properly, it can cause issues. High latency (greater than 250ms), packet jitter (the deviation in latency between packets), or a lack of infrastructure resources (compute, memory, storage IOPs) can all contribute to a poor experience.
SfB has native high availability features, such as application pools and SQL mirroring & AlwaysOn Availability Groups. It also has a native disaster recovery feature, in the form of pool pairing. Note that vMotion can be enabled on SfB VMs, but you have to be mindful of when you execute it.
Best practices for vMotion and DRS for SfB:
- Enable vMotion.
- Set to manual.
- Perform vMotion only when needed and in line with change control.
- Set DRS to partially automated.
- Use anti-affinity rules to keep your SfB pool members apart.
A video demonstrations was shown of what happens to a Skype for Business video conference when the SfB server is vMotioned. The call quality was affected, with the audio and video becoming interrupted for several seconds. This would be considered a problem by most SfB users, especially if the audio becomes interrupted.
Some of the potential pitfalls of virtualizing SfB on vSphere include:
- Forgetting that virtualization is not the same as installing on physical.
- Take advantage of resource pooling, resource abstraction, and utilization “fairness”, to make sure SfB gets the resources it needs.
- More is not always better.
- Size your SfB VMs appropriately, and set up a performance baseline.
- There are more “potential” choke points.
- Virtualization does add complexity, so make sure you know your platform.
Make sure that you use paravirtual SCSI adapters (PVSCSI). They have less CPU overhead and a larger queue depth. If necessary, increase your ring pages, and don’t forget to configure Windows to match your queue depth and ring pages to take full advantage. Ensure that you have the VMware Tools installed in your guest VMs, as they’re necessary to support PVSCSI adapters. Additional SCSI controllers improves concurrency, so make sure you distribute your PVSCSI disks across your SCSI controllers (up to four controllers per VM).
When troubleshooting performance issues in SfB, you should prioritize audio over video quality. This may seem somewhat counter intuitive at first, but for the user experience it doesn’t matter if you can be seen if you can’t be heard.
VMware itself is in the midst of deploying Skype for Business for their own internal use. Why are they doing this? They have over 19,000 people, 30,000 devices, and 90 locations worldwide. They were looking to unify their communications platforms so that they had a single solution for the entire corporation. Their technical requirements included a need for dial-in capabilities, PRI/TDM support for non-SIP areas, integration with an existing Avaya PBX, and the ability to work with existing short dial codes. Skype for Business fit the bill.
So far VMware has two DCs deployed, serving 10,000 users. They have SIP trunks setup for their dial-in numbers. In the future they will be deployed to 8 data centres, serving 30,000 users with enterprise voice service reaching those 90 locations.
VMware released a white paper during VMworld: Best Practices Guide: Virtualizing Microsoft Skype for Business Server on VMware vSphere. If you’re running or are interested in running SfB on vSphere, you need to read this white paper.