• David Wragg's avatar
    vxlan, gre, geneve: Set a large MTU on ovs-created tunnel devices · 7e059158
    David Wragg authored
    Prior to 4.3, openvswitch tunnel vports (vxlan, gre and geneve) could
    transmit vxlan packets of any size, constrained only by the ability to
    send out the resulting packets.  4.3 introduced netdevs corresponding
    to tunnel vports.  These netdevs have an MTU, which limits the size of
    a packet that can be successfully encapsulated.  The default MTU
    values are low (1500 or less), which is awkwardly small in the context
    of physical networks supporting jumbo frames, and leads to a
    conspicuous change in behaviour for userspace.
    
    Instead, set the MTU on openvswitch-created netdevs to be the relevant
    maximum (i.e. the maximum IP packet size minus any relevant overhead),
    effectively restoring the behaviour prior to 4.3.
    Signed-off-by: default avatarDavid Wragg <david@weave.works>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    7e059158
geneve.c 37.7 KB