ntp issue

rajbhatt · ‎03-10-2010

HI,

I am trying to use a cat 6500 switch in 10.80.x.x as a ntp client and the ntp server is the ad server 192.168.0.5

no other device is inbetween .( no access lists blocked)

from the core switch I am able to ping the AD and vice versa. All other devices are picking up time from the AD .

ntp config on the switch

#ntp server 192.168.0.5

I tried using the source interface vlan 2 command and it was of no help.

#sh ntp status
Clock is unsynchronized, stratum 16, no reference clock
nominal freq is 250.0000 Hz, actual freq is 250.0000 Hz, precision is 2**18
reference time is 00000000.00000000 (19:00:00.000 IST Thu Dec 31 1899)
clock offset is 0.0000 msec, root delay is 0.00 msec
root dispersion is 0.00 msec, peer dispersion is 0.00 msec

#sh ntp ass

address ref clock st when poll reach delay offset disp
~192.168.0.5 192.168.0.7 2 6 64 3 6.6 885929 7875.1
* master (synced), # master (unsynced), + selected, - candidate, ~ configured

Also when I do a debug ntp packets and term mon there are no packets

Can some one help me troubleshoot ?

Thanks in advance for ur help

Ganesh Hariharan · ‎03-10-2010

HI,

I am trying to use a cat 6500 switch in 10.80.x.x as a ntp client and the ntp server is the ad server 192.168.0.5

no other device is inbetween .( no access lists blocked)

from the core switch I am able to ping the AD and vice versa. All other devices are picking up time from the AD .

ntp config on the switch

#ntp server 192.168.0.5

I tried using the source interface vlan 2 command and it was of no help.

#sh ntp status
Clock is unsynchronized, stratum 16, no reference clock
nominal freq is 250.0000 Hz, actual freq is 250.0000 Hz, precision is 2**18
reference time is 00000000.00000000 (19:00:00.000 IST Thu Dec 31 1899)
clock offset is 0.0000 msec, root delay is 0.00 msec
root dispersion is 0.00 msec, peer dispersion is 0.00 msec

#sh ntp ***

address ref clock st when poll reach delay offset disp
~192.168.0.5 192.168.0.7 2 6 64 3 6.6 885929 7875.1
* master (synced), # master (unsynced), + selected, - candidate, ~ configured

Also when I do a debug ntp packets and term mon there are no packets

Can some one help me troubleshoot ?

Thanks in advance for ur help

Hi,

Try the following things in order to troubelshoot the NTP issue:-

NTP clock status of 'unsynced' with the following NTP server(s): 192.168.0.5

Check out the following things:-

1. Make sure that above mentioned NTP server(s) is reachable by pinging the server
   IP address(es).
2. Issue the command show ntp status on the server(s) to make sure that NTP server
   has synched itself. If it is not synched, verify the server NTP configuration.
   The show ntp status of the server should display a status of 'sync' before
   clients can sync their clock with the server. If the NTP server is not synchronized
   itself try to disable and re-enable the NTP configuration on the server.
3. Verify that the 'stratum' value configured on the server is valid for your setup.
   Configure a high stratum number to ensure that this router does not override
   the clock on another system with a lower stratum number. The lower stratum number
   indicates a more reliable clock.
4. If authentication is configured between the server and the client, make sure
   that authentication-key number and md5 key value matches. Also, verify that
   the command ntp server {server_address} key {key} is included in the client
   configuration.
5. Make sure that NTP packets are not blocked by the access-list statement.

Hope to Help !!

Remember to rate the helpful post

Ganesh.H

rajbhatt · ‎03-11-2010

HI,

No access list s r blocking . Already checked that before posting

other devices in another locations are synchronizing time to CAM ;s

Ganesh Hariharan · ‎03-11-2010

HI,

No access list s r blocking . Already checked that before posting

other devices in another locations are synchronizing time to CAM ;s

Hi,

Can you share the output of show ntp associations detail also .

Ganesh.H