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New Member

Interface Errors on T1 Link

Dear Friends,

I am facing Issue with one of our cisco 1921/k9 Routers from almost a month now.

ATT will work on the Issue and it will be fine for 1 - 2 days. the again the Error counts keep on Increasing.

Errors are Output drops, Input errors, CRC errors, Overrun, abort, Interfaces resets, Unknown protocol drops, Carrier transitions..

Please help me with this. Thank you.



MPLS Router#sh int s0/0/0
Serial0/0/0 is up, line protocol is up
  Hardware is GT96K with integrated T1 CSU/DSU
  Description: Circuit ID DHEC.930XXXXX
  Internet address is 192.168.XX.XX/30
  MTU 1500 bytes, BW 1536 Kbit/sec, DLY 20000 usec,
     reliability 255/255, txload 3/255, rxload 1/255
  Encapsulation PPP, LCP Open
  Open: IPCP, loopback not set
  Keepalive set (10 sec)
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters 4d14h
  Input queue: 0/75/70/0 (size/max/drops/flushes); Total output drops: 1417
  Queueing strategy: Class-based queueing
  Output queue: 0/1000/0 (size/max total/drops)
  5 minute input rate 1000 bits/sec, 1 packets/sec
  5 minute output rate 20000 bits/sec, 2 packets/sec
     1985213 packets input, 873349930 bytes, 0 no buffer
     Received 0 broadcasts, 1190051 runts, 71 giants, 0 throttles
     2887324 input errors, 254834 CRC, 0 frame, 252 overrun, 0 ignored, 1442187 abort
     2156968 packets output, 1850959693 bytes, 0 underruns
     0 output errors, 0 collisions, 934 interface resets
     6 unknown protocol drops
     0 output buffer failures, 0 output buffers swapped out
     440 carrier transitions
     DCD=up  DSR=up  DTR=up  RTS=up  CTS=up



New Member

 Hi, These kind of errors and



These kind of errors and drops usually indicate an issue at Layer 1 or 2. As per our post everytime AT&T works on this issue and it works fine for a day or two in that case i would suspect some kind of issue at their end. The troubleshooting you can do at your end is to replace the cable and also check to plug this circuit on another interface of a different module on this device, to isolate if the module could be faulty.