diff --git a/sbin/ngcp-network-validator b/sbin/ngcp-network-validator
index a9467433..5ac9c85c 100755
--- a/sbin/ngcp-network-validator
+++ b/sbin/ngcp-network-validator
@@ -124,7 +124,8 @@ foreach my $hostname (sort keys %{$yaml->{hosts}}) {
     foreach my $iface (sort @{$host->{interfaces}}) {
         # Manual interface checks.
         if (defined $host->{$iface}->{ip} and
-            $host->{$iface}->{ip} ne '127.0.0.1') {
+            $host->{$iface}->{ip} ne '127.0.0.1' and
+            $iface !~ m/^dummy/) {
             push @{$dupe_ip{$host->{$iface}->{ip}}}, "$hostname/$iface";
         }
         if (defined $host->{$iface}->{hwaddr} and