bridging ethernets containing vlans,

Julian Elischer julian at elischer.org
Thu Dec 21 17:14:13 PST 2006


If I bridge two ethernets, one with HW_vlan tagging and the other 
without, and there are vlans active on that network, am I right in 
assuming that it requires that the two ethernets need to both have their
HW_vlan capabilities on or off, but that it won't work if they are mixed?

The bridging code seems to turn on and off promiscuous mode for the 
interfaces and bridge_mutecaps() seems to turn on the HX Checksup 
capacity, but there doesn't seem to be any code whereby the
VLAN tagging is enabled or disabled.

This means that bridging a HW-VLAN interface with one that
doesn't support HW vlans will result in just the base packet being
transmitted and the vlan header being dropped.

Am I reading this right?
shouldn't the function bridge_mutecaps() also turn off HW vlan handling?
and is it just a case of adding it to BRIDGE_IFCAPS_MASK?



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