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New Member

Serial0/0:0 is reset, line protocol is down

What it means? I know five possible problem states(up, down, etc.) but about reset I didn't find anything on cisco site. I have 22195 interface resets.

I think, that it means, that I have a problem with E1 controller ( E1 is down), but what kind of problem, I don't know.

sh controllers E1:

Far End Block Errors Detecte

Transmitter is sending remot

Receiver has loss of frame.

Where I can find information about this kind of problem.

Like here:

Thank you.


Re: Serial0/0:0 is reset, line protocol is down

Hi ,

If the channelised E1 is down and i think you are getting " Receiver has loss of frame " under show controllers.

Troubleshooting the Alarm

This section addresses alarms and procedures to correct them. After each step, issue the show controller e1 command to determine if any alarms occur.

Receive Alarm Indication Signal

A receive (rx) Alarm Indication Signal (AIS) means that there is an alarm on the line upstream from the equipment connected to the port. The AIS failure is declared when an AIS defect is detected at the input and still exists after the Loss of Frame (LoF) failure is declared (caused by the unframed nature of the all "1s" signal). The AIS failure is clears when you clear the LoF failure.

To correct rxAIS errors, complete these steps:

Check the show controller e1 slot/port command output to see if the framing format configured on the port matches the framing format of the line.

If not, change the framing format on the controller to match the line.

To change the framing format, issue the framing {crc4 | no-crc4} command in controller configuration mode, for example:

bru-nas-03#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

bru-nas-03(config)#controller e1 0

bru-nas-03(config-controlle)#framing crc4

Contact your service provider to check for an incorrect configuration within the telephone company or a failure in its upstream connections.

Receive Remote Alarm Indication

A Remote Alarm Indication (RAI) means that the far-end equipment has a problem with the signal it is receiving from the local equipment.

The RAI failure is declared when the A-bit (bit three in timeslot zero of frames not containing Frame Alignment Signal [FAS]) becomes one (1). The RAI failure is not declared when a Loss of Signal (LoS) or LoF is detected.

To correct rxRAI errors, complete these steps:

Insert an external loopback cable into the port.

For more information, see the Hard Plug Loopback Tests for E1 Lines document.

Issue the show controller e1 EXEC command to determine if any alarms occur.

If you do not find any alarms, then the local hardware is probably in good condition. In that case, complete these steps:

Check the cabling. Ensure that you have correctly connected the cable between the interface port and the E1 service provider equipment or E1 terminal equipment. Ensure that you have connected the cable to the correct ports. Correct the cable connections if necessary.

Check the cable integrity by looking for breaks or other physical abnormalities in the cable. Ensure the pinouts are set correctly. Replace the cable if necessary.

Check the settings at the remote end and verify that they match your port settings.

If the problem persists, contact your service provider.

Remove the loopback plug, and reconnect your E1 line.

Check the cabling.

Power cycle the router.

Connect the E1 line to a different port. Configure the port with the same settings as the line.

If the problem does not persist, then the fault lies with the port. In this case, complete the following steps:

Reconnect the E1 line to the original port.

Perform a hardware loop test. For more information, see the Hard Plug Loopback Tests for E1 Lines document.

check the below link for info...

Cheers :)


New Member

Re: Serial0/0:0 is reset, line protocol is down

Thank you very much for your answer.

After reboot of the second router - serial is up.

Serial is reset - it means, that we have a problem on the physical layer? Interface is not down, but can't synchronize with another side, that's why we have no the state down, but reset ?

Is it correct?

Hall of Fame Super Gold

Re: Serial0/0:0 is reset, line protocol is down


Reset is a state in which an interface tries to reestablish link by resetting itself and the connected device. Interfaces that are not up/up, do that periodically.

Hope this helps, please rate post if it does!

New Member

Re: Serial0/0:0 is reset, line protocol is down

ok. thanks!

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