Cisco 1720/21 - WIC Problems?


  I have a Cisco 1720 router that is acting a bit flaky.  If I lose power the router boots back up, but the serial interface does not come back up on its own.

  I need to shutdown that interface for about 30 seconds then restart the interface.

  After another 15 seconds it will sync back up with the ISP and it will work fine.


1. Why might that occur?
2. What would be the best method/CLI command to test it?
3. What took the place of the 1720/1721 and/or what are your recommendations for replacing this router with another Cisco router?

This is on a T1 connection.

Thank you for your time.

- Adam
Adam DIT Solutions DeveloperAsked:
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Craig BeckConnect With a Mentor Commented:
The 1841 took the place of the 1720/1.

Now the 1841 is being superseded by the 1921.
vikrantambhoreConnect With a Mentor Commented:
Can you please look on


Adam DIT Solutions DeveloperAuthor Commented:
Thank you for the link, I will look over that information.  Thoughts on the other question?
Adam DIT Solutions DeveloperAuthor Commented:
No objections to closing this question in this manner.  The answers were helpful but only partially complete based on my initial questions.  The end result was a requirement to replace both the WIC and the Router as both were faulty.
QlemoBatchelor, Developer and EE Topic AdvisorCommented:
This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.
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