Cisco 877 - Internal DNS routing issue

Panther256 · ‎07-19-2008

Hello,

I have a long standing isue I could use a hand with. My network topology is:

ADSL connection to a Ciso 877 router. 877 connected to a 3COM baseline switch. All internal network computers and servers connect to the same 3COM switch.

When I try to access my internal web-servers I will sometimes be prompted to login to the 877 instead of being taken to the URL.

I have been living with the problem for about a year now and have overcome it by keeping a HOSTS file updated on all internal network PC's... But I know that shouldn't be necessary.

Anyone have any ideas or comments? I used the 877 wizard initially and if I had no intrnal network it would all work fine.

Thanks

Jason Fraioli · ‎07-19-2008

Please explain your connection to the webserver. Are you trying to access it from the inside or outside?

Explain how your DNS is setup.

Panther256 · ‎07-19-2008

I am trying to connect internally.

We've hypothesized that this may be a DNS issue (forwarders on our internal DNS) but the problem may persist... Still testing. The problem came back after turning off DNS forwarding but then dissappeared a few minutes later.

We'd appreciate any ideas to track down.

Haris P · ‎07-19-2008

Can you post the 877 Configuration . May be there is something in the NAT or DNS .

Make sure that you are able to reach outside without any issue . Also make sure that the DNS configured is resolving correctly on your PC

Regards,

Haris

Panther256 · ‎07-22-2008

Ok,

here is a recent config. I removed all sensitive data and masked the addresses.

Panther256 · ‎07-22-2008

I guess I am leaning heavily towards a DNS issue at this point. Looking back I realized that by utilizing a HOSTS file the problem disappeared completely for the better part of a year on all the affected systems... Unless the workstations were hitting the gateway for DNS instead of the listed DNS servers somehow.

Thank you for helping, I really appreciate it!