ntp does not synchronize

[yuan]

I am trying to synchronize a 3600 router to a remote router (which acts as the ntp server), but failed. This is the "sh ntp associ detail"

10.10.10.1 configured, insane, invalid, unsynced, stratum 16

ref ID 0.0.0.0, time 00000000.00000000 (00:00:00.000 UTC Mon Jan 1 1900)

our mode client, peer mode unspec, our poll intvl 64, peer poll intvl 64

root delay 0.00 msec, root disp 0.00, reach 0, sync dist 0.000

delay 0.00 msec, offset 0.0000 msec, dispersion 16000.00

precision 2**5, version 3

org time 00000000.00000000 (00:00:00.000 UTC Mon Jan 1 1900)

rcv time 00000000.00000000 (00:00:00.000 UTC Mon Jan 1 1900)

xmt time AF67496E.41E85F6A (23:23:26.257 UTC Fri Apr 2 1993)

filtdelay = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

filtoffset = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

filterror = 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0

I could ping 10.10.10.1 with no problem. The only statement in my config is "ntp server 10.10.10.1". Other routers could sync to 10.10.10.1 fine. When I did "debug ntp packet" I don't see anything. What could be wrong?

[glen.grant]

If there are a lot of hops between the boxes try syncing on a device that you know is working that is closer to this device . It doesn't have to go all the way back to the original source , if fact you should keep it synced to a box that is closer so that the ntp traffic doesn't have to traverse the whole network.

[Richard Burts]

My first thought would be the possibility of an access list somewhere on either end router or on some router along the data path which is not allowing this NTP traffic to go through. Can you check for possible access lists?

My second thought is about running debug and getting no output. How long did you let the debug run? (I would think there should be some output every 64 seconds). If you were doing telnet to the router, did you remember to do terminal monitor so that you will see debug output?

Perhaps it would help if you would post the actual configuration of the router.

HTH

Rick

[yuan]

There is not any access-list along the path. I also add in another ntp server statement to pointing to a closer router. I got some results for "debug ntp packets", but not "debug ntp event" or "debug ntp sync". Here they are,

[yuan]

actually, ntp now works after rebooting the router...