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Cisco 851 router clock change problem

Hi all,

We have around 5 remote locations which communicate with a NOC(Network Operations Center) via VSAT link.

On remote location we have Cisco 851 routers. I have tried to change the clock and date of the routers to present day.

But after some time the clock is automatically showing wrong(9th March 2002 in this case).

Kindly suggest.

Thank you in advance.



Cisco 851 router clock change problem

You should consider configuring NTP to keep the time accurate.

Hall of Fame Super Gold

Cisco 851 router clock change problem

850 and 870 does not support NTP, however, it does support SNTP.

Cisco 851 router clock change problem

hi leo,

i don't have any 850s with me, but i would disagree with you on the 870s. it does support both NTP and SNTP.

877#sh ver

Cisco IOS Software, C870 Software (C870-ADVSECURITYK9-M), Version 12.4(11)T3, RELEASE SOFTWARE (fc4)

Technical Support:

Copyright (c) 1986-2007 by Cisco Systems, Inc.

Compiled Thu 12-Jul-07 06:58 by prod_rel_team

ROM: System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE

877 uptime is 1 day, 18 hours, 37 minutes

System returned to ROM by power-on

System restarted at 14:37:46 SGT Thu Dec 8 2011

System image file is "flash:c870-advsecurityk9-mz.124-11.T3.bin"

877(config)#ntp ?

  access-group        Control NTP access

  authenticate        Authenticate time sources

  authentication-key  Authentication key for trusted time sources

  broadcastdelay      Estimated round-trip delay

  clock-period        Length of hardware clock tick

  logging             Enable NTP message logging

  master              Act as NTP master clock

  max-associations    Set maximum number of associations

  peer                Configure NTP peer

  server              Configure NTP server

  source              Configure interface for source address

  trusted-key         Key numbers for trusted time sources

877(config)#sntp ?

  broadcast  Configure SNTP broadcast services

  logging    Enable SNTP message logging

  multicast  Configure SNTP multicast services

  server     Configure SNTP server

Hall of Fame Super Gold

Cisco 851 router clock change problem

You're right about the 870 supporting both.   Mea Culpa.

Cisco 851 router clock change problem

hi sham,

you've probably used the "clock set" command on your 851. the clock info won't be retained if it's rebooted. as suggested by andrew, it's recommended to use NTP.