Think carefully before you chuck out your desktops
Planning for desktop virtualisation
Desktop Virtualisation Desktop virtualisation has its benefits but it is also an important structural shift. This is compounded by other changes likely to take place at the same time, such as a move to Windows 7 or an office move.
When the Co-operative Group decided to migrate some of its 18,000 desktops to virtual desktops and thin clients, it also implemented a hot-desking strategy. It was a lot for users to take on.
“When the plan includes having the office trashed over a weekend and all the desks removed, it is a big culture change,” says David Murrell, head of servers, storage and desktops at the company.
Planning included involving the corporate communications department and posting explanatory videos. Communication may not be the first thing you think of when considering an IT strategy, but it is critical.
We are the champions
Jason Mason, customer support and infrastructure manager at Basildon Borough Council, led the migration of 1,000 users to Citrix thin clients and hot-desking from 2006 to 2008. The council created an internal user group, “Champion users” who are trained in new technology and then help to communicate changes to their colleagues.
The biggest virtualisation challenge is identifying which applications are in use and working out how they will be deployed in the new environment. Mason found vendors less than helpful when asked if their applications would work when virtualised. “We were on our own,” he says.
Tracking down applications proved tricky. “We thought we knew them all, but back in the day when users could install applications locally, even though we had a policy of applications all coming through our department, there were some that slipped through the net,” Masons says.
Chasing the rogues
“It was only once we started the migration that we discovered just how many rogue applications there were dotted around the organisation. We then either had to virtualise them or take them away from people,” says Mason.
The Co-operative Group’s carefully planned its application discovery phase but also made surprising discoveries. “It was a huge eye-opener for us,” says Murrell.
Desktop virtualisation is not just about desktops. “What you need to look at is how much resource will you consume on the data centre side. Consolidation ration is very important,” says Fredrik Sjostedt, an EMEA director at VMWare.
Basildon Borough Council was bitten by this. Partly because of the unexpected number of applications it discovered, its server deployment was not up to the task. It had to upgrade in a hurry, installing additional processors and storage.
The Co-operative Group already had an enterprise infrastructure in place, with HP high availability blades in pairs across two data centres, but still encountered some issues.
One was the performance of its Exchange and Outlook deployment, which consumes a large amount of bandwidth. “We plonked a lot of Fusion-io cards into the blades, and they have proved astonishingly astute choices,” says Murrell.
Careful pacing is another key to success. “At the end of 2009 we did a three-month pilot just to secure the business case,” Murrell says. “We then moved to a business pilot at the start of 2010, which completed early and successfully. We now have about 1,200 users using Xen Desktop.”
Because it's worth it
Migration is ongoing, and he is planning to have up to 6,000 thin-client users. “We build it out 600 users at a time,” he says.
Not everything has to be virtualised. Mac users, road warriors and CAD/CAM users are all candidates for retaining local applications. They may end up as hybrids: at Basildon council, Mac users still have the Citrix client for some standard applications.
Is virtualisation worth it? Mason singles out two areas where it is. One is the flexibility of hot-desking and working from home, and the other is support.
“There has been a massive decrease in support calls,” he says. “When a machine does die we just drop in a new unit and users are up and running within minutes. We used to spend a day or two just setting up applications but we’ve completely eliminated that now.” ®