There is likely no "right" answer for this issue, but for what it's
worth I can report a somewhat related experience I had a few years
ago when updating my PC at home with a new Suse distro. The machine
had been running previous versions of Suse with my Comcast cable
internet service just fine for several years. I downloaded the ISO
from opensuse, burned the DVD, did the install but when it came back
up again the internet service was quite unreliable. It would work for
a few minutes, but then no packets would flow. I happened to run
ifconfig eth0 and it showed an MTU of 576. It seems the version of
the DHCP client that came with the new distro honored the DHCP MTU
option, but Comcast was advertising DHCP offers with an MTU of 576.
Presumably then, your system rejected any incoming packet which was
larger than the 576 byte MTU it got from the Comcast DHCP server..
I can think of two reasons for larger packets to be arriving at your
system then:
1) UDP
2) Broken TCPs ass-u-me-ing a TCP MSS larger than 536 bytes when there
wasn't an MSS option in the SYN(s).
Did your SuSE system send actual TCP MSS options based on the 576 byte MTU?
rick jones
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
