From f92f0a357a4a3b0e38fee727c10f6a0135820e74 Mon Sep 17 00:00:00 2001
From: Thomas Lamprecht <t.lamprecht@proxmox.com>
Date: Wed, 15 Mar 2017 16:47:42 +0100
Subject: [PATCH] remove backup locks when starting all VMs on boot

If on bootup one of our VMs is locked by an backup we safely can
assume that this backup job does not run anymore and that the lock
has no reason anymore and just hinders uptime of services.

As at this time we (the node) have quorum so we may safely assume
that we have a consistent view of the cluster and all our VMs really
belong to us. We just need to ensure that we do not run into an
automatic backup jobs, so execute our code with VZDumps lock or
timeout.
Log in the Task and Sys log that we removed the lock, so that an
admin easily sees that there may be need for cleaning leftovers from
an interrupted backup.

Addresses bug #1024

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
(cherry picked from commit 248b2d361407d07b6d41138ab2912b6a0e66ae6d)
---
 PVE/API2/Nodes.pm | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/PVE/API2/Nodes.pm b/PVE/API2/Nodes.pm
index 101a4f40..eb1ef69b 100644
--- a/PVE/API2/Nodes.pm
+++ b/PVE/API2/Nodes.pm
@@ -1250,6 +1250,7 @@ my $get_filtered_vmlist = sub {
 
 	    $res->{$vmid}->{conf} = $conf;
 	    $res->{$vmid}->{type} = $d->{type};
+	    $res->{$vmid}->{class} = $class;
 	};
 	warn $@ if $@;
     }
@@ -1283,6 +1284,26 @@ my $get_start_stop_list = sub {
     return $resList;
 };
 
+my $remove_locks_on_startup = sub {
+    my ($nodename) = @_;
+
+    my $vmlist = &$get_filtered_vmlist($nodename, undef, undef, 1);
+
+    foreach my $vmid (keys %$vmlist) {
+	my $conf = $vmlist->{$vmid}->{conf};
+	my $class = $conf->{class};
+
+	eval {
+	    if ($class->has_lock($conf, 'backup')) {
+		$class->remove_lock($vmid, 'backup');
+		my $msg =  "removed left over backup lock from '$vmid'!";
+		warn "$msg\n"; # prints to task log
+		syslog('warning', $msg);
+	    }
+	}; warn $@ if $@;
+    }
+};
+
 __PACKAGE__->register_method ({
     name => 'startall', 
     path => 'startall', 
@@ -1334,6 +1355,11 @@ __PACKAGE__->register_method ({
 		} while (!PVE::Cluster::check_cfs_quorum(1));
 		print "got quorum\n";
 	    }
+
+	    eval { # remove backup locks, but avoid running into a scheduled backup job
+		PVE::Tools::lock_file('/var/run/vzdump.lock', 10, $remove_locks_on_startup, $nodename);
+	    }; warn $@ if $@;
+
 	    my $autostart = $force ? undef : 1;
 	    my $startList = &$get_start_stop_list($nodename, $autostart, $param->{vms});