Hi, I've just started building an oVirt farm as a replacement for our existing infrastructure and I'm having issues configuring multiple VLAN bridges with different MTUs. When I try to add a logical network with a VLAN tag + VM Network + MTU 9000 to a bonded interface on my host with only the ovirtmgmt network (MTU 1500, default) it throws up an error message and won't let me continue, error message below: Cannot setup Networks. The following Logical Networks do not have the same MTU value: ovirtmgmt(default), net_bne_vlan10(9000). Eventually, I will want to add more logical networks with the default MTU, so setting the ovirtmgmt MTU to 9000 is unfortunately not going to solve my issue. This is something I can do in vanilla Linux networking where I set the 802.3ad bond to be MTU 9000 and configure two different bridges off that interface to 1500 and 9000, however this does not seem to be possible in the oVirt web interface. I've dug through the Administration guide and feature requests and there doesn't seem to be anything there around using different MTU values for different logical networks. Has anyone been able to successfully do this? The /etc/sysconfig/network-scripts and /var/lib/vdsm/persistence/netconf files seem to get rewritten whenever the vdsm service does anything, so I'm reluctant to edit them manually. The hosts were built using the hosted-engine installer on Fedora 22. The engine is running Fedora 22 also, see below: [root@bne-ovirtengine01 ~]# cat /etc/redhat-release Fedora release 22 (Twenty Two) [root@bne-ovirtengine01 ~]# uname -r 4.0.4-301.fc22.x86_64 oVirt Engine Version: 3.6.0-1.fc22 Any assistance would be appreciated. Cam Wright | Systems Administrator CUTTINGEDGE 90 Victoria St, West End, Brisbane, QLD, 4101 T +61 7 3013 6222 E cwright@cuttingedge.com.au | W www.cuttingedge.com.au /SYD /BNE /MEL /TYO