VMTN Blog

From Slashdot:

To us, the whole point of virtualization is that we have several servers which are mostly idle at all times and completely idle at most times, and for support reasons we're not supposed to be running anything else on the same copy of windows. So we can replace five or six systems with a four-core 1U box with just a few gigabytes of memory, which will recover rack space and reduce power consumption.  ...

One of the other things we prototyped and deployed was 'site services packages' - get GSX (now VMWare Server), stick it on a pair of 2U servers, and attach a storage array to both of them. Then create your 'template' fileserver, DHCP server, print server, proxy, that kind of thing and deploy them to this package. It worked very well indeed - you get a whole new order of magnitude on stability (although to be fair that's in part because we through away the crappy workstations that were doing the 'low intensity' stuff) and was extremely managable, and trivially replacable in the event of a hardware failure. ...

As an experienced sysadmin, my reaction is screw performance. Let's start with reliable and scalable, and then performance just naturally follows, as does a really high grade service.  ...

Another useful guideline: various types of services are impacted differently by being virtualized. Generally, the best candidates for virtualization are ones that spend a lot of time idle. This is actually more common than you might think - people need a server set up for something, can't put it on a pre-existing system for security/compatibility reasons, so they go out and buy a new system which is ten times more powerful than they need. You can put a lot of these kinds of systems on a single, reasonably powerful ESX server.  ...

The best solution is Virtual Infrastructure (used to be ESX). That product tackles most of the failings of VMWare server and fixes them. The only exception is that I still wouldn't run anything I/O heavy on VI. SQL's a no-no. [Actually, lots of people run SQL Server, Oracle, and other databases in virtual infrastructure, and have found that their “I/O heavy” applications run just fine. -jt] Also, if you're not getting the performance from a single web server that you expect, you can easily throw up more web servers. Now, obviously you might get into M$ licensing issues, but that's why you run your web services on Apache :D ...

We've done testing with many tools, and VMware ESX is the fastest true virtualization suite that we've tested.