Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
Community Member

Line Protocol on 1601 up and down


I am having a problem with a 1601 Router. The line protocol goes up and down. I installed another WIC 1T to test if the problem was on the Existing WIC but still have the same problem with the new one.

The IOS version running is 12.0 (3)T . Also when i use another Router on the same Link, it works fine, this means the link is ok, the problem must be with the router.

Anyone knows any known problems with 1601s with IOS 12.0 (3) T ? Help highly appreciated



Community Member

Re: Line Protocol on 1601 up and down


Looks like a software problem, what version is running on the "good" router ?

Community Member

Re: Line Protocol on 1601 up and down

Both router have the same version

Cisco Internetwork Operating System Software

IOS (tm) 1600 Software (C1600-Y-M), Version 12.0(12), RELEASE SOFTWARE (fc1)

Copyright (c) 1986-2000 by cisco Systems, Inc.

Compiled Mon 10-Jul-00 19:59 by htseng

Image text-base: 0x02005000, data-base: 0x0245E484

ROM: System Bootstrap, Version 12.0(3)T, RELEASE SOFTWARE (fc1)

ROM: 1600 Software (C1600-RBOOT-R), Version 12.0(3)T, RELEASE SOFTWARE (fc1)

MTNTEST1 uptime is 17 hours, 39 minutes

System restarted by power-on

System image file is "flash:c1600-y-mz.120-12"

cisco 1601 (68360) processor (revision C) with 6144K/2048K bytes of memory.

Processor board ID 24815082, with hardware revision 00000005

Bridging software.

X.25 software, Version 3.0.0.

1 Ethernet/IEEE 802.3 interface(s)

1 Serial(sync/async) network interface(s)

System/IO memory with parity disabled

8192K bytes of DRAM onboard

System running from RAM

7K bytes of non-volatile configuration memory.

4096K bytes of processor board PCMCIA flash (Read/Write)

Configuration register is 0x2102



Re: Line Protocol on 1601 up and down

can you paste in your config

Community Member

Re: Line Protocol on 1601 up and down

What does the debug int serial0/0 output show?

Make sure if you're logged in through telent you use the term mon command and enable console logging.

conf t

console logging


term mon

debug int serial 0/0

CreatePlease to create content