need help: vpn broken after upgrade to kernel 2.6.21
I'm running debian/lenny on an old Compaq presario 900 laptop that has
become my _desktop_ computer for the past year or so. It's connected
to the internet via a cable modem (pptp vpn, cdc_ether usbnet driver).
It worked better than I expected until I installed the latest
kernel update (package is linux-image-2.6.21-2-k7). With this kernel I
cannot access any external servers (imap, pop3, web) or connect to the box
from outside (ssh and web).
Background: firewall is disabled (i.e. "iptables --list" has nothing
to list), "route" reports similar results on both 2.6.18 (previous
kernel) and 2.6.21, mtu/mru are set to 1492 in ppp options, ping and
dns seem to work.
I've traced network traffic with wireshark, while accessing the web
(www.google.com) with w3m, on both kernels. I'm no expert, but as far
as I can tell network traffic is similar (outgoing _and_ incoming)
upto the point where incoming data (the actual web page) is supposed
to come. With 2.6.21 I see no further incoming packets.
Any ideas? what should I check next?
Who is the culprit? the kernel? my ppp settings?
I'm loosing sleep over this. Please help.