Hi CA,
Thanks for the reply. We managed to separate another route domain along those lines. This particular one stubbornly refused to separate, and in the end we removed it from the config, and rebuilt it more or less from scratch. The rebuilding was initially done in the UI while checking the config files each time we added something. One thing that we noticed was that when creating a vlan in the new route-domain, in the UI it showed as being part of the route-domain, whereas in the config files, it showed as /Common/VLANxyz in /config/bigip_base.conf rather than in the bigip_base.conf in the route domain's directory. Removing the vlan from the Common route domain and adding it to the correct route domain in the config files, and then loading the changed config files from tmsh solved that issue. Once we had the vlans in the correct route domain, we encountered no more problems then typos :-)
Thanks again,
Arjan H