VMware exec says Windows days are numbered (ComputerWorld) [LWN.net]

VMware exec says Windows days are numbered (ComputerWorld)

Posted Aug 23, 2008 19:07 UTC (Sat) by giraffedata (subscriber, #1954)
In reply to: VMware exec says Windows days are numbered (ComputerWorld) by rahvin
Parent article: VMware exec says Windows days are numbered (ComputerWorld)

When you replace 6 servers with 1, what are you shrinking? Same number of MIPS, same amount of memory, same amount of disk space.

I think you're just shrinking physical administrative work. Most of the advertisement I see for doing this combination stresses the reduction of the most expensive resource -- human.

I know combining lets you overlap the reserves that you build into each of the 6 servers, but I think of that as adminstrative cost too, because you build that in to avoid the labor involved in moving physical resources around when the workload changes.

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VMware exec says Windows days are numbered (ComputerWorld)

Posted Aug 23, 2008 21:12 UTC (Sat) by dlang (✭ supporter ✭, #313) [Link]

actually, you are not shrinking your administrative work, you are increasing it.

before you had six copies of an OS to patch and administer, after combining them you now have seven (the six virtual machines and the host OS)

unfortunately many people view virtual machines the way you do and don't ever update them, eventually this is going to start catching up with people.

there are valid reasons to do virtualization
if you have one or more of the following situations

1. you have programs that won't play well with each other that you want to isolate.
2. you have systems that require administrative access from different people that you want to isolate
3. you want to keep each system image as simple as possible to ease administration (accepting the cost of administering more systems)
4. you have systems that have peak uses that don't overlap

and the requirements of the systems are such that a single box can power them all

then it can save you power, rackspace, and possibly money to buy one box to host the other logical systems as virtual machines.

virtualization doesn't solve many problems by itself (in spite of what the vendors claim). yes, it allows you to do graceful migrations from one system to another (by suspending the virtual machine on one box and starting it on another), but only if all the settings are still valid in the new location (same network settings work, no connections to local resources, etc). but this is _not_ the same as making the application highly available, if the first machine crashes the second machine does not have a fully up-to-date copy of the virtual machine to run

VMware exec says Windows days are numbered (ComputerWorld)

Posted Aug 23, 2008 21:45 UTC (Sat) by giraffedata (subscriber, #1954) [Link]

actually, you are not shrinking your administrative work, you are increasing it.

Possibly, but note that I didn't make a statement about the total administrative work. I said you shrink the physical administrative work. This is apparently especially costly for some installations. Taking racks apart and moving memory and CPUs or recabling is more expensive than typing commands from a remote office. Sometimes those commands can even be issued automatically.