how to check this ?
Posted on 2005-04-28
A t1 is provided to a customer.. If the customer's router is turned off or if the T1 cable is bad or removed from the smart jack to the router , I see that "serial is down and line protocol as down". I checked cisco website and they give these
1. Check the LEDs on the CSU/DSU to see whether the CD is active, or insert a breakout box on the line to check for the CD signal.
2. Verify that you are using the proper cable and interface (see your hardware installation documentation).
3. Insert a breakout box and check all control leads.
4. Contact your leased-line or other carrier service to see whether there is a problem.
5. Swap faulty parts.
6. If you suspect faulty router hardware, change the serial line to another port. If the connection comes up, the previously connected interface has a problem.
My end is a 7206 router and it shows " serial is down and line protocol is down".. The telecom company says that they can loop until the smart jack but could not loop to the CSU/DSU.. They obviously cannot if the router is dead or shutdown or the cable from smart jack to router is bad or disconnected..
Is there a way I can loop until the Smartjack from my 7206 for this interface and determine that the problem is the cable or router ?? The whole purpose for me is that If I know the problem is in the router or cable from smartjack , I donot have to open a troubleticket with the telecom company and that can save time.