Cisco 851 router clock change problem

kshambhaskar213 · ‎12-09-2011

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.

Sham

andrew.prince · ‎12-09-2011

You should consider configuring NTP to keep the time accurate.

Leo Laohoo · ‎12-09-2011

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

johnlloyd_13 · ‎12-09-2011

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: http://www.cisco.com/techsupport

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

Leo Laohoo · ‎12-09-2011

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

johnlloyd_13 · ‎12-09-2011

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.