03-16-2011 04:29 AM - edited 03-04-2019 11:46 AM
Hi,
I have a lab environment with 3 routers back to back but one which should be taking the clock (DTE) is up/looped. I have no loop back interfaces on this router and can't understand why this router is reporting back as looped. Can anyone help? I have provided the sh ver info along with interface statuses concerned.
Thanks.
R3-Paris(config-if)#do sh ver
Cisco IOS Software, C2600 Software (C2600-ADVSECURITYK9-M), Version 12.4(15)T8, RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Mon 01-Dec-08 14:23 by prod_rel_team
ROM: System Bootstrap, Version 12.2(8r) [cmong 8r], RELEASE SOFTWARE (fc1)
R3-Paris uptime is 1 hour, 11 minutes
System returned to ROM by power-on
System image file is "flash:c2600-advsecurityk9-mz.124-15.T8.bin"
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
Cisco 2610XM (MPC860P) processor (revision 3.1) with 127422K/3650K bytes of memory.
Processor board ID FOC08360GQ3
M860 processor: part number 5, mask 2
1 FastEthernet interface
1 Serial interface
8 Low-speed serial(sync/async) interfaces
32K bytes of NVRAM.
32768K bytes of processor board System flash (Read/Write)
Configuration register is 0x2102
R3-Paris#sh int s1/0
Serial1/0 is up, line protocol is up (looped)
Hardware is CD2430 in sync mode
Description: Link to R1-NY
Internet address is 192.168.3.2/30
MTU 1500 bytes, BW 128 Kbit/sec, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:00:03, output 00:00:03, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/32 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 96 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1150 packets input, 75700 bytes, 0 no buffer
Received 405 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
1152 packets output, 75788 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
3 unknown protocol drops
3 unknown protocol drops
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
R3-Paris#sh int s1/1
Serial1/1 is up, line protocol is up (looped)
Hardware is CD2430 in sync mode
Description: Link to R2-chicago
Internet address is 192.168.2.2/30
MTU 1500 bytes, BW 128 Kbit/sec, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:00:06, output 00:00:06, output hang 00:47:37
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/2/32 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 96 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
335 packets input, 23290 bytes, 0 no buffer
Received 335 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
398 packets output, 25107 bytes, 0 underruns
0 output errors, 0 collisions, 64 interface resets
1 unknown protocol drops
1 unknown protocol drops
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
R3-Paris#
03-16-2011 05:30 PM
Make sure encapsulation and clock speeds match on both ends.
03-16-2011 06:24 PM
The clocks have been checked again to ensure R3 is DTE. Please see below the controller details and the encapsulation types on each. I tried another serial interface which worked quite alright I now suspect if it's the NM-8A/S card that's problematic. If you can think of anything else please let me.
R3-Paris#sh controller s1/0 | i DTE
idb 0x83BB12AC, buffer size 1524, V.35 DTE cable
R3-Paris#sh int s1/0 | i Encap
Encapsulation HDLC, loopback not set
R3-Paris#sh controller s1/1 | i DTE
idb 0x83BB5F14, buffer size 1524, V.35 DTE cable
R3-Paris#
R3-Paris#sh int s1/1 | i Encap
Encapsulation HDLC, loopback not set
R3-Paris#
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