datacenter config: avoid writing out default MAC prefix

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

diff --git a/src/PVE/DataCenterConfig.pm b/src/PVE/DataCenterConfig.pm
index e3c8817b3fa1ccb74ce22d532a67a8fbca4e5597..c80872ce5ce445e2c2bf14da1186e8ade3ff273e 100644 (file)
--- a/src/PVE/DataCenterConfig.pm
+++ b/src/PVE/DataCenterConfig.pm
@@ -7,6 +7,9 @@ use PVE::JSONSchema qw(get_standard_option parse_property_string register_standa
 use PVE::Tools;
 use PVE::Cluster;
 
+# MA-L (large) assigned by IEEE
+my $PROXMOX_OUI = 'BC:24:11';
+
 my $crs_format = {
     ha => {
        type => 'string',
@@ -402,9 +405,9 @@ my $datacenter_schema = {
            optional => 1,
            type => 'string',
            format => 'mac-prefix',
-           default => 'BC:24:11',
+           default => $PROXMOX_OUI,
            description => "Prefix for the auto-generated MAC addresses of virtual guests. The"
-               ." default 'BC:24:11' is the OUI assigned by the IEEE to Proxmox Server Solutions"
+               ." default '$PROXMOX_OUI' is the OUI assigned by the IEEE to Proxmox Server Solutions"
                ." GmbH for a 24-bit large MAC block. You're allowed to use this in local networks,"
                ." i.e., those not directly reachable by the public (e.g., in a LAN or behind NAT)."
                ,
@@ -417,7 +420,7 @@ my $datacenter_schema = {
                ." their virtual guests, it's highly recommended that you extend the default MAC"
                ." prefix, or generate a custom (valid) one, to reduce the chance of MAC collisions."
                ." For example, add a separate extra hexadecimal to the Proxmox OUI for each cluster,"
-               ." like `BC:24:11:0` for the first, `BC:24:11:1` for the second, and so on.\n"
+               ." like `$PROXMOX_OUI:0` for the first, `$PROXMOX_OUI:1` for the second, and so on.\n"
                ." Alternatively, you can also separate the networks of the guests logically, e.g.,"
                ." by using VLANs.\n\nFor publicly accessible guests it's recommended that you get"
                ." your own https://standards.ieee.org/products-programs/regauth/[OUI from the IEEE]"
@@ -495,8 +498,7 @@ sub parse_datacenter_config {
 
     # it could be better to track that this is the default, and not explicitly set, but having
     # no MAC prefix is really not ideal, and overriding that here centrally catches all call sites
-    $res->{mac_prefix} = $datacenter_schema->{properties}->{mac_prefix}->{default}
-       if !defined($res->{mac_prefix});
+    $res->{mac_prefix} = $PROXMOX_OUI if !defined($res->{mac_prefix});
 
     if (my $crs = $res->{crs}) {
        $res->{crs} = parse_property_string($crs_format, $crs);
@@ -574,6 +576,10 @@ sub write_datacenter_config {
        $cfg->{console} = 'html5';
     }
 
+    if (defined($cfg->{mac_prefix}) && uc($cfg->{mac_prefix}) eq $PROXMOX_OUI) {
+       delete $cfg->{mac_prefix}; # avoid writing out default prefix
+    }
+
     if (ref(my $crs = $cfg->{crs})) {
        $cfg->{crs} = PVE::JSONSchema::print_property_string($crs, $crs_format);
     }