interfaces: do not warn about FD if it was not set explicitly

As that would be weird, the use explicitly did not configure it,
which is OK, and we'd then warn due to *our* fallback to `0`.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/src/PVE/INotify.pm b/src/PVE/INotify.pm
index 22f27f1ebc695a9b3136ca92ccc7b55f42116bd5..4ff63e891c291ddf58840a029c9b1a3aded9da1f 100644 (file)
--- a/src/PVE/INotify.pm
+++ b/src/PVE/INotify.pm
@@ -1259,12 +1259,16 @@ sub __interface_to_string {
        $raw .= "\tbridge-stp $br_stp\n";
        $done->{bridge_stp} = 1;
 
-       my $br_fd = defined($d->{bridge_fd}) ? $d->{bridge_fd} : 0;
-       # 0 is only allowed when STP is disabled
-       if ($no_stp || ($br_fd >= 2 && $br_fd <= 30)) {
-           $raw .= "\tbridge-fd $br_fd\n";
-       } else {
-           warn "'$iface': ignoring 'bridge_fd' value '$br_fd', outside of allowed range 2-30\n";
+       # NOTE: forwarding delay must be 2 <= FD <= 30 if STP is enabled
+       if (defined(my $br_fd = $d->{bridge_fd})) {
+           if ($no_stp || ($br_fd >= 2 && $br_fd <= 30)) {
+               $raw .= "\tbridge-fd $br_fd\n";
+           } else {
+               # only complain if the user actually set a value, but not for default fallback below
+               warn "'$iface': ignoring 'bridge_fd' value '$br_fd', outside of allowed range 2-30\n";
+           }
+       } elsif ($no_stp) {
+           $raw .= "\tbridge-fd 0\n";
        }
        $done->{bridge_fd} = 1;