Hi,
I have an existing VPLS network that is working great with a MTU of 1540 active on all my bridge links enabling full-sized 1514 byte ethernet frames to be encapsulated in VPLS tunnels.
I just acquired a new leased L2 link between two points in my network over an infrastructure that currently only supports an MTU of 1514.

Is it possible to have my routers on either end of this link fragment VPLS packets before sending out across this link to allow me to still encapsulate 1514 byte ethernet frames, albeit fragmented?

Thanks,
Matt

Does this help you? http://wiki.mikrotik.com/wiki/Manual:VPLS_Control_Word

You might pull an EoIP-Tunnel trough the leased-line.
Then Tunnel the MPLS/VPLS through this EoIP-Tunnel.

The EoIP-Tunnel will enlarge the MTU by fragmenting and reassmbling the MPLS/VPLS frames.

Does this help you? http://wiki.mikrotik.com/wiki/Manual:VPLS_Control_Word

Sure does!

The answer was to /interface vpls set <interface> use-control-word=yes on both routers
use-control-word=default is the default and that wasn't doing it.