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The Trouble with Virtualization - Cranky IT Staffs
lgmac writes "A new survey on the results of Enterprise use of virtualization shows that the process is seeing wide and appreciative use. Technical hurdles are obviously the biggest problem facing corporate IT shops. Just the same, political squabbles among IT staffers fighting for turf after being forced to work together in new ways seems to be a going concern as well. 'Technical woes rank higher--to be expected when CIOs deploy a new technology such as virtualization. However, the politics pain many of you. Remember, virtualization not only asks people to cede some control over their physical server kingdoms, but also asks IT experts from different realms to work more closely together.'"
34% of surveyed companies have been running virtualized desktops? Putting aside that that number doesn't seem to square with the "Virtual Desktops a Hard Sell" table below, does that seem likely?!?
What I'm listening to now on Pandora...
On the VMware side, there's several options. VMware's Consolidated Backup does exactly this. Also you can look at ESX Ranger.
It may be more practical to back up the system from within the VM, i.e. treat it as if it weren't a VM. By definition this will be on a live system.
Another option:
Have your VM use a checkpoint disk. Once a day shut down the VM, merge the changes from this week into the checkpoint disk, and restart the VM. This may take anywhere from a few minutes to tens of minutes. Restart the VM. Back up the checkpoint-disk image.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
*facepalm* I sometimes forget how stupid people can be.
Personally, what I've found to work great with virtualization is consolidating all the dozens of little low-load servers. It helps with power consumption and heat output, as well as hardware costs. For a major company-wide high-load system, virtualization is absolutely not what I would be looking at. It's also fantastic for testing environments.
I don't know about you, but my servers run on the power of cotton candy and happy thoughts. -Anonymous Coward
VMware has multiple ways to balance and protect resources. You can set hard limits on VM resource utilization, ensuring that one machine can never take over a certain percentage of CPU, memory and even network bandwidth. VMs can also be given "shares", which determine priority over resources. In a contention for resources, the VM with the highest number shares is given immediate access to what it needs, with the lower share VMs splitting what's left over. This is the recommended way to handle it, as it gives you the best overall hardware utilization across your entire implementation.
Starting in VI3, VMware also introduced the ability for VMs to migrate automatically across an entire farm of hosts, based on server load. In my experience, with very little tweaking, VMware does a very good job of fairly balancing resources.
Say you have a need to add another fax board(or whatever) to the virtualized x86 server, to find that they stuck some mission critical Virtual Environment on the Server and It CAN'T come down for another 2 weeks.
:) If you need to do work on a physical server [say hardware replacement, firmware upgrade, etc], you put that server into maintenance mode. VMWare will automatically and **transparently** migrate the running VMs onto the remaining servers. You can then power off the physical server, do whatever you need to do, and power it back on. When it comes back up, take it out of maintenance mode, and VMWare will automatically start migrating VMs back onto it to balance the load.
Aside from another poster's excellent point about not virtualizing servers that require specialized hardware, you're missing another point of the virtualized servers.
In the case of VMWare ESX server, you'd use VMotion to solve this problem. Say you have a cluster of 3 or 4 physical servers running some number of VMs. Hopefully you're not dumb enough to have all those servers running anywhere near 100%.
Nobody will notice the fact that their mission critical server just moved from one box to another. Worst case, if your servers were already a bit too heavily loaded, some applications will slow down a bit while you're doing maintenance, but a temporary slow down is a lot better than having an application completely down every time you have to upgrade firmware or replace a stick of RAM.
As an added bonus, if you so choose, VMotion can automatically balance the VMs at all times, so if one particular VM is suddenly requiring a large amount of resources, VMotion can migrate it to a less heavily loaded box, or migrate other less needy VMs to another box to free resources for the VM that needs it. This is great for handling short-term usage fluctuations, or can even be scripted to adjust for known, regular usage peaks.
That's not to say there aren't downsides to virtualization, but the situation you described isn't one of them.
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ESX3 is Linux based however ESX3i is not. It is a pure hypervisor checking in at about 32MB.