From 1c8dc310b3f118fa686166b3b4639de82a2ec969 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>
---
 PVE/API2/Nodes.pm | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/PVE/API2/Nodes.pm b/PVE/API2/Nodes.pm
index d78f49c0..03f97bff 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 $@;
     }
@@ -1286,6 +1287,26 @@ 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', 
@@ -1337,6 +1358,11 @@ __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});