One NIC can I setup VMBR & use Jumbo Frames for the SAN?


New Member
Mar 7, 2013
I did a silly thing and purchased a bunch of systems after reading a few threads on here from unixsurplus. Great price -but... the 2nd NIC on all 4 servers in this Dell system ( 4 boards made by Supermicro - go figure) do not work.There is no MAC address in the bios either... So I am stuck with 1 NIC for each system within this 2 U case Is it possible to use JumboFrames and use the Bridge? My hope is that the virtual serves can talk out and serve data at 1500mtu (normal) while I can use 9000 for the storage array. Sadly I cannot find the expansion cards for these units. can someone give me the For a dummy setup ? I am not a linux admin - but learning . . .


Famous Member
Apr 2, 2010
this should works:

auto eth0
iface eth0 inet static
        address X.X.X.X
        netmask X.X.X.X
        mtu 9000

iface vmbr0 inet manual
       bridge_ports eth0
       bridge_stp off
       bridge_fd 0
       post-up  ifconfig vmbr0 mtu 9000


Sep 11, 2010
FYI, I tried this approach and it didn't work well for me. My OpenVZ image worked OK, but a KVM vm didn't.

From reading other threads, I set it up like this, and it works:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet manual

auto vmbr0
iface vmbr0 inet static
bridge_ports eth0
bridge_stp off
bridge_fd 0
pre-up ifconfig eth0 mtu 9000

When I do an ifconfig, I see MTU of 9000 on both eth0 and vbmr0.


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