[pve-devel] [PATCH/RFC qemu-server 3/3] Fix checks for transfering replication state/switching job target

[Fabian Ebner]

When there are offline disks, $self->{replicated_volumes} will be
auto-vivified to {} by the check:
next if $self->{replicated_volumes}->{$volid}
in sync_disks() and then {} would evaluate to true in a boolean context.

Now the replication job information is retrieved once in prepare,
and the job information rather than the information if volumes
were replicated is used to decide whether to make the calls or not.

For offline migration to a non-replication target, there are no
$self->{replicated_volumes}, but the state should be transfered nonetheless.

For online migration to a non-replication target, replication
is broken afterwards anyways, so it doesn't make much of a difference
if the state is transferred or not.

Signed-off-by: Fabian Ebner <f.ebner at proxmox.com>
---

Hope I'm not misinterpreting when these calls should or shouldn't
be made.

 PVE/QemuMigrate.pm | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/PVE/QemuMigrate.pm b/PVE/QemuMigrate.pm
index a20e1c7..6097ef2 100644
--- a/PVE/QemuMigrate.pm
+++ b/PVE/QemuMigrate.pm
@@ -220,6 +220,10 @@ sub prepare {
     # test if VM exists
     my $conf = $self->{vmconf} = PVE::QemuConfig->load_config($vmid);
 
+    my $repl_conf = PVE::ReplicationConfig->new();
+    $self->{replication_jobcfg} = $repl_conf->find_local_replication_job($vmid, $self->{node});
+    $self->{is_replicated} = $repl_conf->check_for_existing_jobs($vmid, 1);
+
     PVE::QemuConfig->check_lock($conf);
 
     my $running = 0;
@@ -227,10 +231,7 @@ sub prepare {
 	die "can't migrate running VM without --online\n" if !$online;
 	$running = $pid;
 
-	my $repl_conf = PVE::ReplicationConfig->new();
-	my $is_replicated = $repl_conf->check_for_existing_jobs($vmid, 1);
-	my $is_replicated_to_target = defined($repl_conf->find_local_replication_job($vmid, $self->{node}));
-	if ($is_replicated && !$is_replicated_to_target) {
+	if ($self->{is_replicated} && !$self->{replication_jobcfg}) {
 	    if ($self->{opts}->{force}) {
 		$self->log('warn', "WARNING: Node '$self->{node}' is not a replication target. Existing " .
 			           "replication jobs will fail after migration!\n");
@@ -362,9 +363,7 @@ sub sync_disks {
 	    });
 	}
 
-	my $rep_cfg = PVE::ReplicationConfig->new();
-	my $replication_jobcfg = $rep_cfg->find_local_replication_job($vmid, $self->{node});
-	my $replicatable_volumes = !$replication_jobcfg ? {}
+	my $replicatable_volumes = !$self->{replication_jobcfg} ? {}
 	    : PVE::QemuConfig->get_replicatable_volumes($storecfg, $vmid, $conf, 0, 1);
 
 	my $test_volid = sub {
@@ -489,7 +488,7 @@ sub sync_disks {
 	    }
 	}
 
-	if ($replication_jobcfg) {
+	if ($self->{replication_jobcfg}) {
 	    if ($self->{running}) {
 
 		my $version = PVE::QemuServer::kvm_user_version();
@@ -523,7 +522,7 @@ sub sync_disks {
 	    my $start_time = time();
 	    my $logfunc = sub { $self->log('info', shift) };
 	    $self->{replicated_volumes} = PVE::Replication::run_replication(
-	       'PVE::QemuConfig', $replication_jobcfg, $start_time, $start_time, $logfunc);
+	       'PVE::QemuConfig', $self->{replication_jobcfg}, $start_time, $start_time, $logfunc);
 	}
 
 	# sizes in config have to be accurate for remote node to correctly
@@ -1193,7 +1192,7 @@ sub phase3_cleanup {
     }
 
     # transfer replication state before move config
-    $self->transfer_replication_state() if $self->{replicated_volumes};
+    $self->transfer_replication_state() if $self->{is_replicated};
 
     # move config to remote node
     my $conffile = PVE::QemuConfig->config_file($vmid);
@@ -1202,7 +1201,7 @@ sub phase3_cleanup {
     die "Failed to move config to node '$self->{node}' - rename failed: $!\n"
         if !rename($conffile, $newconffile);
 
-    $self->switch_replication_job_target() if $self->{replicated_volumes};
+    $self->switch_replication_job_target() if $self->{replication_jobcfg};
 
     if ($self->{livemigration}) {
 	if ($self->{stopnbd}) {
-- 
2.20.1