From mboxrd@z Thu Jan 1 00:00:00 1970
Return-Path: <shanreich@lana.proxmox.com>
Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68])
(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)
key-exchange X25519 server-signature RSA-PSS (2048 bits))
(No client certificate requested)
by lists.proxmox.com (Postfix) with ESMTPS id 6E790EC43
for <pve-devel@lists.proxmox.com>; Mon, 12 Dec 2022 14:43:15 +0100 (CET)
Received: from firstgate.proxmox.com (localhost [127.0.0.1])
by firstgate.proxmox.com (Proxmox) with ESMTP id 53D1F53CD
for <pve-devel@lists.proxmox.com>; Mon, 12 Dec 2022 14:43:15 +0100 (CET)
Received: from lana.proxmox.com (unknown [94.136.29.99])
by firstgate.proxmox.com (Proxmox) with ESMTP
for <pve-devel@lists.proxmox.com>; Mon, 12 Dec 2022 14:43:14 +0100 (CET)
Received: by lana.proxmox.com (Postfix, from userid 10043)
id 603532C28DA; Mon, 12 Dec 2022 14:43:14 +0100 (CET)
From: Stefan Hanreich <s.hanreich@proxmox.com>
To: pve-devel@lists.proxmox.com
Date: Mon, 12 Dec 2022 14:43:12 +0100
Message-Id: <20221212134312.257662-3-s.hanreich@proxmox.com>
X-Mailer: git-send-email 2.30.2
In-Reply-To: <20221212134312.257662-1-s.hanreich@proxmox.com>
References: <20221212134312.257662-1-s.hanreich@proxmox.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
X-SPAM-LEVEL: Spam detection results: 0
AWL -0.328 Adjusted score from AWL reputation of From: address
BAYES_00 -1.9 Bayes spam probability is 0 to 1%
KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment
KAM_LAZY_DOMAIN_SECURITY 1 Sending domain does not have any anti-forgery
methods
NO_DNS_FOR_FROM 0.001 Envelope sender has no MX or A DNS records
RDNS_NONE 0.793 Delivered to internal network by a host with no rDNS
SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record
SPF_NONE 0.001 SPF: sender does not publish an SPF Record
Subject: [pve-devel] [PATCH pve-guest-common 1/1] partially fix #2530:
snapshots: add pre/post/failed-snapshot hooks
X-BeenThere: pve-devel@lists.proxmox.com
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Proxmox VE development discussion <pve-devel.lists.proxmox.com>
List-Unsubscribe: <https://lists.proxmox.com/cgi-bin/mailman/options/pve-devel>,
<mailto:pve-devel-request@lists.proxmox.com?subject=unsubscribe>
List-Archive: <http://lists.proxmox.com/pipermail/pve-devel/>
List-Post: <mailto:pve-devel@lists.proxmox.com>
List-Help: <mailto:pve-devel-request@lists.proxmox.com?subject=help>
List-Subscribe: <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>,
<mailto:pve-devel-request@lists.proxmox.com?subject=subscribe>
X-List-Received-Date: Mon, 12 Dec 2022 13:43:15 -0000
This commit adds hooks to the snapshotting process, which can be used
to run additional setup scripts to prepare the VM for snapshotting.
Examples for use cases include:
* forcing processes to flush their writes
* blocking processes from writing
* altering the configuration of the VM to make snapshotting possible
The prepare step has been split into two parts, so the configuration
can be locked a bit earlier during the snapshotting process. Doing it
this way ensures that the configuration is already locked during the
pre-snapshot hook. Because of this split, the VM config gets written
in two stages now, rather than one.
In case of failure during the preparation step - after the lock is
written - error handling has been added so the lock gets released
properly. The failed-snapshot hook runs when the snapshot fails, if
the pre-snapshot hook ran already. This enables users to revert any
changes done during the pre-snapshot hookscript.
The preparation step assumes that the hook does not convert the
current VM into a template, which is why the basic checks are not
re-run after the pre-snapshot hook. The storage check runs after the
pre-snapshot hook, because the hook might get used to setup the
storage for snapshotting. If the hook would run after the storage
checks, this becomes impossible.
cfs_update() gets called after every invocation of a hookscript, since
it is impossible to know which changes get made by the hookscript.
Doing this ensures that we see the updated state of the CFS after the
hookscript got invoked.
Signed-off-by: Stefan Hanreich <s.hanreich@proxmox.com>
---
src/PVE/AbstractConfig.pm | 49 ++++++++++++++++++++++++++++++++++-----
1 file changed, 43 insertions(+), 6 deletions(-)
diff --git a/src/PVE/AbstractConfig.pm b/src/PVE/AbstractConfig.pm
index a0c0bc6..3bff600 100644
--- a/src/PVE/AbstractConfig.pm
+++ b/src/PVE/AbstractConfig.pm
@@ -710,8 +710,7 @@ sub __snapshot_prepare {
my $snap;
- my $updatefn = sub {
-
+ my $run_checks = sub {
my $conf = $class->load_config($vmid);
die "you can't take a snapshot if it's a template\n"
@@ -721,15 +720,21 @@ sub __snapshot_prepare {
$conf->{lock} = 'snapshot';
- my $snapshots = $conf->{snapshots};
-
die "snapshot name '$snapname' already used\n"
- if defined($snapshots->{$snapname});
+ if defined($conf->{snapshots}->{$snapname});
+
+ $class->write_config($vmid, $conf);
+ };
+ my $updatefn = sub {
+ my $conf = $class->load_config($vmid);
my $storecfg = PVE::Storage::config();
+
die "snapshot feature is not available\n"
if !$class->has_feature('snapshot', $conf, $storecfg, undef, undef, $snapname eq 'vzdump');
+ my $snapshots = $conf->{snapshots};
+
for my $snap (sort keys %$snapshots) {
my $parent_name = $snapshots->{$snap}->{parent} // '';
if ($snapname eq $parent_name) {
@@ -753,7 +758,32 @@ sub __snapshot_prepare {
$class->write_config($vmid, $conf);
};
- $class->lock_config($vmid, $updatefn);
+ $class->lock_config($vmid, $run_checks);
+
+ eval {
+ my $conf = $class->load_config($vmid);
+ PVE::GuestHelpers::exec_hookscript($conf, $vmid, "pre-snapshot", 1);
+ };
+ my $err = $@;
+
+ PVE::Cluster::cfs_update();
+
+ if ($err) {
+ $class->remove_lock($vmid, 'snapshot');
+ die $err;
+ }
+
+ eval {
+ $class->lock_config($vmid, $updatefn);
+ };
+ if (my $err = $@) {
+ my $conf = $class->load_config($vmid);
+ PVE::GuestHelpers::exec_hookscript($conf, $vmid, "failed-snapshot");
+ PVE::Cluster::cfs_update();
+
+ $class->remove_lock($vmid, 'snapshot');
+ die $err;
+ }
return $snap;
}
@@ -837,11 +867,18 @@ sub snapshot_create {
if ($err) {
warn "snapshot create failed: starting cleanup\n";
+
+ PVE::GuestHelpers::exec_hookscript($conf, $vmid, "failed-snapshot");
+ PVE::Cluster::cfs_update();
+
eval { $class->snapshot_delete($vmid, $snapname, 1, $drivehash); };
warn "$@" if $@;
die "$err\n";
}
+ PVE::GuestHelpers::exec_hookscript($conf, $vmid, "post-snapshot");
+ PVE::Cluster::cfs_update();
+
$class->__snapshot_commit($vmid, $snapname);
}
--
2.30.2