In the last few years we’ve been migrating all our servers over to KVM virtual machines running on a Ubuntu servers. I’ve come to love VM’s. There seems to be compelling reasons for using them.
- You can install a new VM very quickly without having to setup new hardware.
- You can control the resources for each VM really easily – scaling memory and cpu. So it you can use resources more effectively.
- You can backup an VM server really easily.
- However, the best longterm reason is that you can move the VM’s really easily. For example, if you move to a new server hosting company, you just stop the VM instance, copy it to the new server host and restart it again. Brilliant. Even if you’re renting a dedicated server and are only going to use all it’s resources for one server, I highly recommend setting up the dedicated server as a host and running vm on top. This single VM can use all the cpu and memory. The overhead is very low and when you come to more to another dedicate host it will save you hours of configuration – just copy the VM.
We have avoided using cloud hosting (such as Amazon, Rackspace or Linode) for several reasons:
- Your data isn’t in your control. I want my data on my hard drives.
- Unlike the simplicity of raw or qcow2 disk images, you can’t move to an cloud hosted server very easily. Yes, I know Openstack is supposed to solve this problem – but in the meantime have you tried migrating from Linode? Basically, you need to reinstall.
- If you have more than one server or need lots of space / cpu power then it is often cheaper hosting it yourself.
Basically, I think that VM’s rock. What do you think?