Hello, I'm looking for a way to prevent the users/administrators of our virtual machines to change their ip. One of the interesting solutions I stumbled upon is the isolatedprivatevlan hook[1] I installed the hook via yum, added the Custom VM Setting ("UserDefinedVMProperties=isolatedprivatevlan=^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2}),(?:[0-9]{1,3}\.){3}[0-9]{1,3}$"), that I'm not sure if it's correct as it was written up quickly. Now when I set the custom setting via the panel and try to start the VM I get the following error: "VM TestVM is down. Exit message: XML error: Invalid specification of multiple <filterref>s in a single <interface>." If I read the wiki[1] correcty the <interface> should have multiple <filterrefs> when this hook is activated. So I'm wondering if the hook is simply out of date/not working or am I missing something else? I'm running oVirt 3.4.2-1.el6 on CentOS 6 (everything up to date). Any help would be greatly appreciated, (including other ways of preventing the VM ip changes from users) Črnko [1] - http://www.ovirt.org/VDSM-Hooks/isolatedprivatevlan