Odd Network Behavior

[mwidner]

Forgive me for this subject - I'm not sure how else to phrase it. I searched the forums, but even that was difficult. I'm not even sure which thread to put this into.

Anyway, we are a central site and we have a branch office that is connected by fiber on a VLAN. The router is here, and they have a switch at the branch. We use one of the FastEthernet ports on the Cisco 3825 router to designate the VLAN, their ip range, dhcp pool etc.

For some reason, people at the branch cannot access Comcast e-mail. They get to the site, but their mail will not open. One day last week, a staff member tried to go to a web site, but it times out. We tried a ping, a tracert from the branch office, but all timed out. Yet, from the central site, we were able to access ALL the above. Same router...

Any ideas? TIA!

m.

 

[cajuntank]

So with you using the term VLAN, what equipment do you have on the branch side that's recognizing this VLAN tag?

 

[mwidner]

Thanks for your input...

We have a Cisco Catalyst 3500.

 

[cajuntank]

Trying to understand why you are introducing another layer of complexity by establishing VLAN tagging in the first place unless you are trying to tag multiple VLANs down to the branch.

If you are coming off a FE port on the Cisco, it's already a routed port. You might have this configured one of two ways on the 3500 side. You might have the 3500 as a layer 2 switch only and have a default gateway defined as the 3825 FE interface or you might have a IP address defined on a VLAN interface and have IP routing turned on. This would require routes to be defined on both layer 3 appliances. If you want, please post a snippit of your configs of both appliances (change whatever private info you don't want known) so I can understand how you are currently setup.

 

[C3rv32a2]

Is your COmcast in the same vlan ass the branch office? have you tried configuring the port where you connect the branch office as trunk?