Morning Due to in increasing number of lustre oss''s and cluster compute nodes, I had to move them onto different subnet (though connected via the same switch). I have 3 switches in our topology, 1 top switch with trunked links down to two bottom switches. The luster/compute nodes are then connected to each of the bottom switches (all eth0 to one switch and eth1 to the other). Now, I want to setup the network on the lustre/compute nodes to ensure that traffic doesn''t go via the trunks. To do this, I''m using route to explicitly direct traffic out the appropriate NIC. route add -net 172.16.0.0/24 eth0 # lustre nic1 route add -net 172.16.1.0/24 eth1 # lustre nic2 route add -net 172.16.4.0/24 eth0 # compute nic1 route add -net 172.16.5.0/24 eth1 # compute nic2 now, does this play well with lnet? Am I getting what I want? Thanks Stu. -- Dr Stuart Midgley sdm900@gmail.com