rolling snapshot no appears more on Xen Orchestra

[vbits]

@danp Yes, thank you. I also found that post. What a pity, and can anyone think of a script to be able to do it by cron or some other alternative? I'm very bad with that...

[olivierlambert]

But why not using Rolling snapshot from backup view? That's the way to use it.

[vbits]

@olivierlambert ah wow!!
I had not looked at it there! I just looked at jobs and schedules.
thank you very much!

Sorry for the oversight

[vbits]

@vbits One last question, can you tell me please how much on average or what percentage of the VM is the size of a snapshot? (with and without memory)

[olivierlambert]

Depends on the SR type (thin or thick).

[vbits]

@olivierlambert thick

[olivierlambert]

So let's take an example of a 100GiB virtual disk (full at 10GiB).

Before the snapshot, you are using 100GiB on your SR.

Just after the snapshot, you'll use 200GiB (and few MiB for the snapshot). After a bit, the base copy will be deflated to 10GiB, so you'll use 110GiB roughly. But at the time of the snap, you need roughly double of disk space available on your storage.

[vbits]

@olivierlambert Interesting, understood, thank you again.
So the snapshot itself doesn't take up hardly any space, just a few megabytes as you said.
I guess the rolling feature will do the snapshots one by one.
So it would be enough for me to have as free space a little more than the biggest virtual disk of the host.
Or am I wrong?
Right now I don't know if I have any SR thin on any other host as well, but would the situation apply?

[vbits]

@vbits PS. Assuming I do a rolling snapshot schedule job of all VMs on the host of course.

[olivierlambert]

Thin will have an active disk only the size used. So instead of using 100GiB, you are using 10GiB, and with a snap, only 10GiB and few KiB.