NTP not updating - Page 2

Charlie Jones · ‎01-08-2013

Last night we upgraded one of our offices 3560 (WS-C3560-24PS) to 12.2(55) SE6. With these switches, NTP is no longer working. The NTP server is a router at this office. Switches at this office that were not upgraded (3750) are getting NTP normally. Below is a copy of the show ntp association and show ntp status. I have removed the ntp lines from the switch configuration and re-added them, and that has not changed anything.

Any suggestions?

address ref clock st when poll reach delay offset disp

~172.28.119.1 0.0.0.0 16 - 64 0 0.0 0.00 16000.

* master (synced), # master (unsynced), + selected, - candidate, ~ configured

Clock is unsynchronized, stratum 16, no reference clock

nominal freq is 119.2092 Hz, actual freq is 119.2092 Hz, precision is 2**17

reference time is 00000000.00000000 (18:00:00.000 CST 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

I enabled NTP debugging for events, packets, and clock synchro.

.Jan 8 12:40:20.821 CST: org D496E694.D23A9C1E (12:40:20.821 CST Tue Jan 8 2013)

.Jan 8 12:40:20.821 CST: rec D496EA23.CD71F8DD (12:55:31.802 CST Tue Jan 8 2013)

.Jan 8 12:40:20.821 CST: xmt D496EA23.CD72AD94 (12:55:31.802 CST Tue Jan 8 2013)

.Jan 8 12:40:20.821 CST: inp D496E694.D2F5B99A (12:40:20.824 CST Tue Jan 8 2013)

.Jan 8 12:41:24.826 CST: NTP: xmit packet to 172.28.119.1:

.Jan 8 12:41:24.826 CST: leap 3, mode 3, version 3, stratum 0, ppoll 64

.Jan 8 12:41:24.826 CST: rtdel 0000 (0.000), rtdsp 10001 (1000.015), refid 00000000 (0.0.0.0)

.Jan 8 12:41:24.826 CST: ref 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:41:24.826 CST: org 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:41:24.826 CST: rec 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:41:24.826 CST: xmt D496E6D4.D380FC51 (12:41:24.826 CST Tue Jan 8 2013)

.Jan 8 12:41:24.826 CST: NTP: rcv packet from 172.28.119.1 to 10.19.0.111 on Vlan1:

.Jan 8 12:41:24.826 CST: leap 0, mode 4, version 3, stratum 4, ppoll 64

.Jan 8 12:41:24.826 CST: rtdel 0B6E (44.647), rtdsp 1A4B (102.707), refid AC1C9605 (172.28.150.5)

.Jan 8 12:41:24.826 CST: ref D496EA59.756DBDF0 (12:56:25.458 CST Tue Jan 8 2013)

.Jan 8 12:41:24.826 CST: org D496E6D4.D380FC51 (12:41:24.826 CST Tue Jan 8 2013)

.Jan 8 12:41:24.826 CST: rec D496EA63.CEE98503 (12:56:35.808 CST Tue Jan 8 2013)

.Jan 8 12:41:24.826 CST: xmt D496EA63.CEEA3978 (12:56:35.808 CST Tue Jan 8 2013)

.Jan 8 12:41:24.826 CST: inp D496E6D4.D440210D (12:41:24.829 CST Tue Jan 8 2013)

.Jan 8 12:42:28.822 CST: NTP: xmit packet to 172.28.119.1:

.Jan 8 12:42:28.822 CST: leap 3, mode 3, version 3, stratum 0, ppoll 64

.Jan 8 12:42:28.822 CST: rtdel 0000 (0.000), rtdsp 10001 (1000.015), refid 00000000 (0.0.0.0)

.Jan 8 12:42:28.822 CST: ref 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:42:28.822 CST: org 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:42:28.822 CST: rec 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:42:28.822 CST: xmt D496E714.D3885867 (12:42:28.826 CST Tue Jan 8 2013)

.Jan 8 12:42:28.822 CST: NTP: rcv packet from 172.28.119.1 to 10.19.0.111 on Vlan1:

.Jan 8 12:42:28.822 CST: leap 0, mode 4, version 3, stratum 4, ppoll 64

.Jan 8 12:42:28.822 CST: rtdel 0B6F (44.662), rtdsp 1B72 (107.208), refid AC1C9605 (172.28.150.5)

.Jan 8 12:42:28.822 CST: ref D496EA99.75D55A7C (12:57:29.460 CST Tue Jan 8 2013)

.Jan 8 12:42:28.822 CST: org D496E714.D3885867 (12:42:28.826 CST Tue Jan 8 2013)

.Jan 8 12:42:28.822 CST: rec D496EAA3.CF1E056B (12:57:39.809 CST Tue Jan 8 2013)

.Jan 8 12:42:28.822 CST: xmt D496EAA3.CF1EBAA7 (12:57:39.809 CST Tue Jan 8 2013)

.Jan 8 12:42:28.822 CST: inp D496E714.D43215B2 (12:42:28.828 CST Tue Jan 8 2013)

.Jan 8 12:43:32.819 CST: NTP: xmit packet to 172.28.119.1:

.Jan 8 12:43:32.819 CST: leap 3, mode 3, version 3, stratum 0, ppoll 64

.Jan 8 12:43:32.819 CST: rtdel 0000 (0.000), rtdsp 10001 (1000.015), refid 00000000 (0.0.0.0)

.Jan 8 12:43:32.819 CST: ref 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:43:32.819 CST: org 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:43:32.819 CST: rec 00000000.00000000 (18:00:00.000 CST Thu Dec 31 1899)

.Jan 8 12:43:32.819 CST: xmt D496E754.D30205DD (12:43:32.824 CST Tue Jan 8 2013)

.Jan 8 12:43:32.819 CST: NTP: rcv packet from 172.28.119.1 to 10.19.0.111 on Vlan1:

.Jan 8 12:43:32.819 CST: leap 0, mode 4, version 3, stratum 4, ppoll 64

.Jan 8 12:43:32.819 CST: rtdel 0B73 (44.724), rtdsp 1AC6 (104.584), refid AC1C9605 (172.28.150.5)

.Jan 8 12:43:32.819 CST: ref D496EAD9.7633439A (12:58:33.461 CST Tue Jan 8 2013)

.Jan 8 12:43:32.819 CST: org D496E754.D30205DD (12:43:32.824 CST Tue Jan 8 2013)

.Jan 8 12:43:32.819 CST: rec D496EAE3.CEC7C08E (12:58:43.807 CST Tue Jan 8 2013)

.Jan 8 12:43:32.819 CST: xmt D496EAE3.CEC87126 (12:58:43.807 CST Tue Jan 8 2013)

.Jan 8 12:43:32.819 CST: inp D496E754.D387299F (12:43:32.826 CST Tue Jan 8 2013)

NormMuelleman · ‎01-09-2013

This may be off-topic for you Charlie, but it's just a thought...

Last week I had noticed our NTP had failed. No upgrades/changes had been made.

Low in behold, our firewall team decided our exemption was expired and BLOCKED NTP at the firewall...sigh...

Got it unblocked, and NTP working like a champ again....funny thing was I was able to ping the NTP source (of course), and didnt think about it for a while. Then it kinda hit me upside the head that maybe port 123 was being blocked. Sure was!

Any chance NTP got blocked from a firewall or access llist without someone mentioning it? Or did you upgrade your firewall software and it get blocked somehow? Just trying to help with some out-the-box suggestions!

glen.grant · ‎01-09-2013

The ip default gateway statement is only used if routing is turned off on the switches otherwise you would use a default static route pointing to the routing gateway address.

Charlie Jones · ‎01-16-2013

After staring at this and looking through everything, the problem wasn't on the switch side but on the router side. We tried rebooting one of the switches in question and when that didn't work, we looked at the router at the site. As I mentioned, one of the routers at this branch handled ntp for all of our switches. When we looked at the router, we discovered it had not synched for 26 days. Last night, we did a reboot on this router, and NTP is working correctly now at this site.

Thanks to everyone for their input on this. I certainly appreciate it.

RilENTNetwork@ril.com · ‎06-14-2018

Try deleteing these commands:

ntp clock-period

ntp access-group peer

Worked for me!!

Regards,

Mihir

<mihir7716@gmail.com>