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New Member

Help with CISCO 2921 ISR Configuration

Hello, all, we just bought a 2921 with the following modules:

  1. 4 port clear channel T1/E1 HWIC
  2. SM-ES3G-24-P: EtherSwitch

I read some CISCO documents, and not be able to find what I need. I would prefer all instructions from you are for CLI interface.

This is my first time to deal directly with T1, WIC and 2921 etc. The following is what I get from ATT, IP masked

IP Address Block
IP Address:

WAN Link Details:
WAN Link IP Address:
AR Serial INT IP Address:
CR Serial INT IP Address:
WAN Link Subnet Mask:

My questions:

A: how do I configure T1, what does "AR, CR" stands for, and do I need to use both IP addresses?

    What is the WAN Link IP for?

B: We have two T1 lines, so I should plug them both to the WIC, say port 0 and port 1, how to configure them?

C: how do I access the firewall from the command line?

D: I followed T1/E1 HWIC installation guide, and as soon as I add channel-group to the controller t1, the serial interface went down?

I would highly appreciate your help to get me started, either providing some easy to follow instructions, or an example configureation file that is similiar to my setup.



Help with CISCO 2921 ISR Configuration

Hi Bin,

CR- Customer router  AR- Access router. Check the below link for config ex:

If you have dual T1s, how you plan to use them- bundle (PPP) or production/backup?

If this is your first time, I suggest you to hire a consultant.



New Member

Help with CISCO 2921 ISR Configuration


how do I access the firewall from the command line?

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