Hi there. I'm currently evaluating Nutanix and AHV, and had a newbie question regarding snapshot reversions. I read about AHV's "redirect on write" approach to snapshots, and am unsure regarding the nature of the dependance between snapshots. For example, say I'm testing something on a server, and I create snaps A, B, C and D (in that order). Could I revert to any of these snaps and in any order, and would deleting a snapshot in the chain affect my ability to revert to an earlier snap?
Have you had a chance to look at the Nutanix Bible? In particular, I'm wondering if this section helps any - http://nutanixbible.com/#anchor-snapshots-and-clones-73
Let me know Thanks
deleting a snapshot in the middle of the chain is typically not a good idea, but if the delta model works as designed it should remove the changes made between snap 1 and snap 3 when deleting snap2 in snap 3.
So if snap 1 was base with apps installed
snap 2 is configuration changes to base apps
snap 3 is configuration changes to base os
then deleting snap 2 would result in base with apps installed and changes to OS.
My experience however is this creates issues if the later snaps depended on or changed files implimented in snap 2.
From what I've tested you can use any of the snapshots at the time. We use Data Protection Groups for some of our DR and have scheduled to have several copies and different schedule intervals and we have been able to recover to any of the saved snapshots.
@RI_SysAdmin yes you could revert any snap in any order
let say you have snap1 snap2 snap3 snap4
last snap should be on snap4 and you can restore snap1
from restored snap1 you also can go restore snap4