I'd basically like to second the "request" or question: I started on an /28 allocation, because that was the only available at the time. In the mean-time I managed to get hold of a full class C net, which I'd like to use for the VMs on a 3-node HCI with a couple of extra compute and gluster storage nodes added in the course of its life, without having to rebuild from scratch. I'd be happy to just add the extra range on the hosts in parallel or I'd do a move, but somehow I'm afraid that IPs or/or DNS names are baked into configuration files if now downright database tables, to make such a thing easy or possible. I tried just adding the extra subnet on /etc/sysconfig/network-scripts/ifcfg-ovirtmgmt and that works for a while, but it seems that VDSM is regularly overwriting that from data stored in /var/lib/vdsm/persistence/netconf/nets and that syntax there may not support the sort of syntax that the ifcfg scripts have for additional IP subnets (PREFIX instead of NETMASK, IPADDR[n]) etc. I can't really go into VLANs, because servers in that environment are access mode exclusively.