<html><head>
<meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type">
</head><body bgcolor="#FFFFFF" text="#000000">I believe a single file
does exist for the snapshot but it isn't what you think. I believe, if
ploop snapshotting is what I believe it to be, that file is only used to
log the changes to the filesystem while preserving the root.hdd file
(your original filesystem). Once a snapshot is created, the original
root.hdd goes untouched, any changes to the filesystem go into the file
designated for the snapshots (root.hdd.uuid). Then when a new snapshot
file is created, the previous snapshot file is preserved and the new
snapshot file gets all the changes. The top delta file keeps track of
the snapshots.<br>
<br>
<blockquote style="border: 0px none;"
cite="mid:CAMOhFjERAN=ep2z18eD8Gw-pLY++hXgoUonikg8msXN8UwOwMw@mail.gmail.com"
type="cite">
<div style="margin:30px 25px 10px 25px;" class="__pbConvHr"><div
style="display:table;width:100%;border-top:1px solid
#EDEEF0;padding-top:5px"> <div
style="display:table-cell;vertical-align:middle;padding-right:6px;"><img
photoaddress="sgbarrett@gmail.com" photoname="Simon Barrett"
src="cid:part1.05030705.05040200@virtualcomplete.com"
name="compose-unknown-contact.jpg" height="25px" width="25px"></div> <div
style="display:table-cell;white-space:nowrap;vertical-align:middle;width:100%">
<a moz-do-not-send="true" href="mailto:sgbarrett@gmail.com"
style="color:#737F92
!important;padding-right:6px;font-weight:bold;text-decoration:none
!important;">Simon Barrett</a></div> <div
style="display:table-cell;white-space:nowrap;vertical-align:middle;">
<font color="#9FA2A5"><span style="padding-left:6px">Tuesday, November
18, 2014 6:02 AM</span></font></div></div></div>
<div style="color:#888888;margin-left:24px;margin-right:24px;"
__pbrmquotes="true" class="__pbConvBody"><div dir="ltr"><div>> I'm
not quite following all of your statements. Specifically, I don't</div><div>>
see why you think you need a base AND a first snapshot. One snapshot is</div><div>>
sufficient for later restoring. Also, I don't think you need to</div><div>>
understand the underlying architecture in order to successfully use</div><div>>
snapshots (it might be helpful or interesting, but not really</div><div>>
necessary). The command 'snapshot-switch' reliably restores the state
of</div><div>> the CT it had at the time when you created the
snapshot. It's as simple</div><div>> as that. Also, when deleting
snapshots, vzctl auto-magically does the</div><div>> right thing in
that it merges or deletes when it is appropriate without</div><div>>
affecting the other snapshots of the given container.</div><div>></div><div><br></div><div>Sorry
about kicking this off again, but this hit to me over the weekend and
it cleared things up for me. Please, someone, correct me if I'm wrong.</div><div><br></div><div>As
I understand it now, no single file corresponds to a snapshot and to
think of it that way will lead you to do something silly with your
data. A snapshot is an event. If you want to think of it in terms of
files, it's the gap between the root.hdd and the delta. It's a like a
HUP in I/O gives you a spot to go back to. When you delete a snapshot,
you're deleting the event and this means the files that are either side
of that discontinuity will be merged/healed.</div><div><br></div><div>When
you mount a snapshot, for example when doing file based backup (<a
moz-do-not-send="true" href="https://openvz.org/Ploop/Backup">https://openvz.org/Ploop/Backup</a>)
you're not actually mounting a snapshot because there is no snapshot
file to mount; you're mounting the pre-snapshot data.</div><div><br></div><div><br></div><div>Simon</div></div>
<div>_______________________________________________<br>Users mailing
list<br><a class="moz-txt-link-abbreviated" href="mailto:Users@openvz.org">Users@openvz.org</a><br><a class="moz-txt-link-freetext" href="https://lists.openvz.org/mailman/listinfo/users">https://lists.openvz.org/mailman/listinfo/users</a><br></div></div>
</blockquote>
</body></html>