VMware Communities: Message List - Virtual files and their purposes

Re: Virtual files and their purposes

Dave.Mishchenko — Wed, 29 Oct 2008 19:21:28 GMT

Snapshots are a good way to do backup and they're great it you want to rollback from a change / patch / etc. My concern was over the size the of snapshot - i.e. 270 GB snapshot file on your 800 GB vmdk. At some point you'll want to commit the snapshot and if something screws up there seems to have been a lot of data that will have changed. Plus the snapshot will take a very long time to commit back to the main vmdk.

The vmsn file by the way is a snapshot of the memory of the VM when you took the snapshot. If you were to revert back to the snapshot then the VM would load up the memory file and the VM would start exactly as it was when you took the snapshot.

Re: Virtual files and their purposes

jmueske — Wed, 29 Oct 2008 18:43:16 GMT

Hi Dave,

Thanks for the quick response. I was using the snapshot as a roll back in case I mussed something up, or installed something which proved not good. If you don't want to run snapshots much, I take it the purpose is not for backup. What's the reccomended archive and backup method?

Regards,

John

Re: Virtual files and their purposes

Dave.Mishchenko — Wed, 29 Oct 2008 18:24:16 GMT

The vswp file is the memory swap file for the VM. The file is created when you power on a VM and is equal to the memory of the VM minus any memory reservation that you have set. ESXi will use this file should it need to swap contents of the VMs memory to disk should the ESXi host run low on physical memory. The other vmdk files are snap shots and in general you don't want to run them for a long time or let them grow that large.

Virtual files and their purposes

jmueske — Wed, 29 Oct 2008 16:34:25 GMT

Hi,

I've configured a Windows server with a 40GB local drive and 800GB data drive (virtual disk files with the *.vmdk extension). I can see these files in the datastore browser, see attached. However I also have some large files taking up space which are weird sizes. I suspect they have to do with the snapshot I've taken, can someone confirm this? The suspicious files are circled.

Regards,

John