Problem with reaching specific web-sites, 871 router

[northtexasnetworks]

My customer has a CISCO871 router connected to a DSL bridge,  Everything works fine EXCEPT there are a few web-sites the users cannot reach, such as msn.com.  When I connect my laptop directly to the bridge and set it up with the static IP, I can go to any web-site, but when I connect the router to the bridge, there are a few web-sites that cannot be reached.   The firewall ACL is just basic stuff, not excluding any specific sites.

I have never seen a problem like this, anyone have any ideas?

Thanks,

Mitchell Smith

[sean_evershed]

Have you tried removing the firewall ACL as a test?

[Reza Sharifi · Accepted solution]

Have a look at this link and command:

ip tcp adjust-mss

http://www.cisco.com/en/US/docs/ios/12_2t/12_2t4/feature/guide/ft_admss.html#wp1047645

[northtexasnetworks]

Thanks for your help!  I am sure this will cure the problem as we are using PPPoE with a Dialer interface just like the example.

[Yasir Ashfaque]

Hi,

for PPPoE, check if your customer has configured the MTU to 1492 at the dialer interface and tcp mss adjust to 1452 at the dialer or LAN facing interface.