SR space occupied by backup snapshots

[manilx]

@manilx P.S. Clicking on one disk of a VM to understand it I get:
The disk, 2 snapshots and a base copy?
What's the base copy?
In this case a 200GB disk is using 4x200GB? Can't be. Totally confused.

[Gheppy]

base copy it's the reference, it's that vdi that contains all the information before snopshoot.
If you use the LVM format it is normal to be like this, if you use the ext4 (vhd) format it will only be the difference.
Because you don't have space, use the ext4 format for SR

[manilx]

@Gheppy OK..... Weird.
What's the advantage/disadvantge of LVM vs ETX4 and vice versa then?

[Gheppy]

@manilx
I chose ext4, precisely so as not to waste unnecessary space

[manilx]

@Gheppy OK. Thx.

[olivierlambert]

It's not 4x200GiB, even in thick provisioned storage. The size you side is the total disk size, not the space used.

[manilx]

@olivierlambert Sorry but I don't understand this. Call me stupid....

In the first screenshot of the disks in the SR:
I have the disk + 2 snapshots of the same size as the disk. So I understand the space used is not 3x disk size? What is it then?

I'm asking this all because after 2 running backups I'm running out of disk space.
These are the SR's:

If I need to reformat in ext4 we have to redo this.
Going forward we are migrating our 2 main big hosts from vmware and I need to understand this before as once formatted it is a PITA to reformat when there are vm's.

Really appreciate your clarification on this as it is very different from esx.

[manilx]

@manilx
E.g. This is the space used by one disk... It's using 500+ GB (it's a 300GB VM disk)

[olivierlambert]

There's a different between the space allocated and the space used.

If you are doing a migration from VMware without spending any time to learn, maybe you need professional service to be assisted?

[manilx]

@olivierlambert We are being assisted by professional services but they are also new to xcp-ng.

I'm ready to learn!! Everyone had a start....

[manilx]

@manilx P.S: This is why we only migrated a small instance.... To learn!

[olivierlambert]

You are assisted by whom? We did not yet opened our certification program (but it should be a matter of few months)

[manilx]

@olivierlambert Here in Portugal: Securnet

But I'd appreciate it a lot if you could clarify this for me.

[manilx]

@manilx We're a 15year vmware client..... Still with 2 years of contract. But still wanting to migrate to you.

[olivierlambert]

And I'm happy you are doing this ! Let me check about your partner for the integration (I want to be sure you are working with skilled people)

[manilx]

@olivierlambert They are! But new to xcp-ng.

[olivierlambert]

Okay let's continue by private chat on the partner thing.