Internet routing issue

[Vishnu Reddy]

I have 2 remote sites. Its been long since I have been troubleshooting on this but no concrete results. One site can open www.dell.com but the other site couldn't open the www.dell.com. I tried pointing to different DNS servers but no results. When I telnet www.dell.com 80 works fine for the site where it opens www.dell.com and telnet doesn't work where it doesn't open the dell website. Traceroute works on windows to www.dell.com without any issues completely for each site. Since they are two different remote locations ISPs are different as well.

Guys need a help on how to troubleshoot/approach this issue. These are plain ISR G2 routers with no firewalls attached as well disabled windows firewall where the tests are done. Tried removing access-list on the outside interface facing internet still doesn't work.

[e.ciollaro]

Hi,

did you try to type the IP address instead of www.dell.com ?

[Vishnu Reddy]

It doesn't work when used with IP address.

[e.ciollaro]

but you can ping or trace from the same host, correct ? If so, it seems to be a problem related to the protocol, more then to routing. Could you post the router config ?

Did you try to ping form ISR router using the internal LAN as source ?

[Vishnu Reddy]

Nope I can't ping the dell.com using source interface as internal. But I do also see that their no nat translation when trying to open the website in the browser.

Thanks for your reply

[e.ciollaro]

> Nope I can't ping the dell.com using source interface as internal.

but you can ping/trace from the hosts on LAN, right ?

> But I do also see that their no nat translation when trying to open the website in the browser.

If so, you should have pubblic ip address on LAN, is it the case ?

In any case if you trace form a host to dell.com it can't be a routing problem; I think the most probable causes are:

- some kind of filter  (may be on switch)

- problem with NAT (if in use)

Could you post the ISR config ?

[Roberto Kippins]

Hi is dell.com the only site that you cannot access?

[Vishnu Reddy]

I cannot access dell.com and adobe.com. These are the websites i cannot access. Rest of all the websites can be access from these sites. There are like more than 5 sites accross the europe with different ISPs we are facing this issue.

[Roberto Kippins]

Could be that you public ip or the entire subnet is blocked.

[Vishnu Reddy]

Initially I thought of that as the possibility. Ruled out when it was happening at different sites with ADSL but one with the Cable worked fine.