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strange clockrate in serial interface

fsoffia
Level 1
Level 1

hallo,

I'm configuring a cisco1841 ios 12.4(1a)

with a WIT-1T serial interface for FR access. It must act as DTE so I don't configure a "clock rate" on Serial0/0/0.

The router at the moment is not connected to DCE and no cable on interface.

When I issue "sh run" in Serial0/0/0 does appear a "clockrate 2000000" that I never have configured.

interface Serial0/0/0

description FR service

bandwidth 128

no ip address

encapsulation frame-relay IETF

load-interval 30

ntp disable

keepalive 8

no fair-queue

clockrate 2000000 <--- ???

frame-relay traffic-shaping

!

interface Serial0/0/0.51 point-to-point

description link fr con bassano cir 128k

bandwidth 128

ip address 172.16.1.22 255

etc.

what about that unwanted clockrate ?

best regards

francesco

6 Replies 6

spremkumar
Level 9
Level 9

hi

AFAIK untill unless you manually configure the clockrate on the interface it will not be there by default.

As you mite be knowing you can remove off the same using no clockrate 2000000 command.

Once you are done you can do recheck by reseting the router after saving the config so as to check the repetation of the command in the config.

regds

hi,

in my config file, the "clockrate 2000000" command is not present !!

I did "no clockrate 2000000" but it does not disappear from running-config.

I never had this problem before.

Where it come from ?

best regards

Hi,

One option you have is to save a copy of the config to a text file and then go into config mode and enter in the following:

default interface Serial0/0/0

That will restore the interface to its defaults. Then, paste the relevant bits of the interface config back in.

Hope that helps - pls rate the post if it does.

Paresh

Hello,

in addition to the other posts, I think the Setup Command Facility puts that clockrate on the router by default. I have seen numerous routers configured with the Setup Command Facility, and the serial interfaces look like this by default:

interface Serial0/2/0

no ip address

no ip redirects

no ip unreachables

no ip proxy-arp

ip route-cache flow

shutdown

clockrate 2000000

no cdp enable

Check the link below and scroll down a few lines, it shows you that the Setup Command Facility sets the clockrate to 2000000 by default.

Configuration: Basic Software Configuration Using the Setup Facility

1- or 2-Port Serial Interface Configuration

http://www.cisco.com/en/US/products/ps5854/prod_configuration_guide09186a00802c35e7.html#wp33861

Regards,

Nethelper

hi,

the config was done using CLI and a text-file, not using the setup-facility.

I tried to connect the V.35 DTE cable and reload the router and the "clockrate 2000000" DISAPPEAR from sh run.

!

interface Serial0/0/0

description service FR

bandwidth 128

no ip address

encapsulation frame-relay IETF

load-interval 30

ntp disable

keepalive 8

no fair-queue

frame-relay traffic-shaping

!

interface Serial0/0/0.51 point-to-point

description link fr con bassano cir 128k

bandwidth 128

ip address 172.16.1.22 25

etc.

milano-1841#sh controllers s0/0/0

Interface Serial0/0/0

Hardware is GT96K

DTE V.35 clocks stopped.

idb at 0x62A4A698, driver data structure at 0x62A51E04

wic_info 0x62A524

I think that if the interface s0/0/0 does not know what will be her type she set itself to DCE with a default clokrate.

THIS BEHAVIOR IS DIFFERENT FROM THE OTHER ROUTERS I HAVE SEEN BEFORE. FOR EXAMPLE I TRIED WITH A CISCO2621 IOS 12.2(12) SAME CONFIG FILE, SAME WIC-1T AND NO SERIAL CABLE ATTACHED -> IN SH RUN DOES NOT APPEAR ANY CLOCKRATE !!

Please give me your opinion or experience.

thanks

best regards

francesco

You may very well be correct on this.

The type of interface (DTE/DCE) is determined by the cable. A WIC-device that is not connected is therefore in an undefined state.

You may try to reproduce the setup and then connect a DTE-cable to the router, without doing anything on the cli. This should suffice to make the clockrate disappear.

Regards,

Leo

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