Re: VLAN MTU Problem?

On Fri, Mar 25, 2005 at 08:06:29AM -0800, Derek Fedel wrote:
> Hi All,
> 
> I'm experiencing this strange issue where I can send an email fine
> from either VLAN as long as its text only, no attachment, but when I
> try to send with an attachment, it just hangs the email server process
> (qmail-smtpd in this case). Is this something that may be caused by an
> MTU problem?

Everyone calls it an MTU problem but it has nothing to do with
transmission and everything to do with reception. The NIC/driver
combination you're using cannot receive fullsize tagged packets.
(since they are up to four bytes larger than the plain ethernet spec
maximum)


> I've got a RealTek 8100 series card and a eepro100 as my
> two VLAN interfaces, and this phenomenon doesnt occur at an office
> that we don't have VLANs.

Make sure you're using the e100 driver rather than the eepro100
driver for the Intel card.


//Peter