diff --git a/inventory/host_vars/internetx01.fedoraproject.org b/inventory/host_vars/internetx01.fedoraproject.org
index 285aac2ce4..a09c771918 100644
--- a/inventory/host_vars/internetx01.fedoraproject.org
+++ b/inventory/host_vars/internetx01.fedoraproject.org
@@ -4,6 +4,7 @@ br0_ipv4_gw: 85.236.55.1
 br0_ipv4_nm: 28
 br0_ipv6: 2001:4178:2:1269::10
 br0_ipv6_gw: 2001:4178:2:1269::1
+br0_ipv6_nm: 64
 br0_port0_mac: '{{ mac0 }}'
 datacenter: internetx
 dns1: 8.8.8.8