[Click] Problem sending VLAN tagged packets

[Nicholas Weaver]

On Tue, Feb 13, 2007 at 11:16:52PM -0800, Eddie Kohler composed:
> My guess this is a bug in Linux or the underlying operating system.  You're 
> using userlevel ToDevice; the element has no idea of any "maximum length", 
> it just reports errors returned by the send() system call.  So someone 
> somehwere forgot that VLAN-enabled packet socket interfaces have a 
> different MTU than plain ol ethernet.

So related question, is there some flag perhaps that I'm forgitting on
ifconfig?



> E
> 
> 
> Nicholas Weaver wrote:
> >Stupid error (probably) on my part somewhere...
> >
> >OK, I'm trying to add a VLAN tag on all packets.  Of course, for MTU
> >packets, this adds 4 bytes.
> >
> >So I'm getting a bunch of 
> >ToDevice(eth5) send: Message too long
> >errors from these now "overlength" packets.
> >
> >However, these are NOT overlength, as MTU for ethernet is +4 bytes for
> >VLAN tagged packets.  Suggestions?
> >

-- 
Nicholas C. Weaver                               nweaver at icsi.berkeley.edu
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