This is a XenServer 7.1 CU1
host. NTP should behave as in any other Linux distro
. We have configured /etc/ntp.conf
with following servers (have tried other servers with similar results and these servers worked in another environment:
server 0.north-america.pool.ntp.org
server 1.north-america.pool.ntp.org
server 2.north-america.pool.ntp.org
server 3.north-america.pool.ntp.org
After restarting the service, we check stats:
[root@c0101 ~]# ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
*tock.usshc.com .GPS. 1 u 56 64 1 32.936 36.036 0.000
www.tripout.tec 128.233.154.245 2 u 56 64 1 82.397 46.653 0.000
+t2.time.bf1.yah 98.139.133.62 2 u 57 64 1 17.589 26.316 0.000
mirrors.switch. 206.108.0.134 2 u 55 64 1 63.777 57.423 0.000
From this, I can see that tock.usshc.com
was chosen (has * star symbol), the poll is at 62s which is minimum due to bad source, the offset is high (since I checked on a server on a different environment and it shows only -0.81), the jitter is 0 which looks odd as in all cases I have seen at least one low number such as 0.1
and the delay looks normal.
After about ten minutes, no servers had chosen (no * symbol) due to "bad sources", also the offset and jitter look pretty bad:
[root@c0101 ~]# ntpq -c peers
remote refid st t when poll reach delay offset jitter
==============================================================================
tock.usshc.com .GPS. 1 u 52 64 205 32.952 6021.94 4422.72
www.tripout.tec 128.233.154.245 2 u 64 64 377 82.473 5880.01 3724.85
t2.time.bf1.yah 98.139.133.62 2 u 3 64 377 17.812 6647.80 3704.53
mirrors.switch. 206.108.0.134 2 u 1 64 377 63.746 6678.59 3723.43
Here is the ntp log, which I am having a hard time understanding.
[root@c0101 ~]# cat /var/log/ntp.log
14 Sep 12:01:20 ntpd[3914]: ntp_io: estimated max descriptors: 1024, initial socket boundary: 16
14 Sep 12:01:20 ntpd[3914]: Listen and drop on 0 v4wildcard 0.0.0.0 UDP 123
14 Sep 12:01:20 ntpd[3914]: Listen and drop on 1 v6wildcard :: UDP 123
14 Sep 12:01:20 ntpd[3914]: Listen normally on 2 lo 127.0.0.1 UDP 123
14 Sep 12:01:20 ntpd[3914]: Listen normally on 3 xapi1 10.131.250.22 UDP 123
14 Sep 12:01:20 ntpd[3914]: Listening on routing socket on fd #20 for interface updates
14 Sep 12:01:20 ntpd[3914]: 0.0.0.0 c016 06 restart
14 Sep 12:01:20 ntpd[3914]: 0.0.0.0 c012 02 freq_set kernel 500.000 PPM
14 Sep 12:01:21 ntpd[3914]: 0.0.0.0 c61c 0c clock_step +1014.260362 s
14 Sep 12:18:15 ntpd[3914]: 0.0.0.0 c614 04 freq_mode
14 Sep 12:18:16 ntpd[3914]: 0.0.0.0 c618 08 no_sys_peer
14 Sep 12:19:39 ntpd[3914]: ntpd exiting on signal 15
14 Sep 12:19:39 ntpd[4689]: ntp_io: estimated max descriptors: 1024, initial socket boundary: 16
14 Sep 12:19:39 ntpd[4689]: Listen and drop on 0 v4wildcard 0.0.0.0 UDP 123
14 Sep 12:19:39 ntpd[4689]: Listen and drop on 1 v6wildcard :: UDP 123
14 Sep 12:19:39 ntpd[4689]: Listen normally on 2 lo 127.0.0.1 UDP 123
14 Sep 12:19:39 ntpd[4689]: Listen normally on 3 xapi1 10.131.250.22 UDP 123
14 Sep 12:19:39 ntpd[4689]: Listening on routing socket on fd #20 for interface updates
14 Sep 12:19:39 ntpd[4689]: 0.0.0.0 c016 06 restart
14 Sep 12:19:39 ntpd[4689]: 0.0.0.0 c012 02 freq_set kernel 500.000 PPM
14 Sep 12:19:40 ntpd[4689]: 0.0.0.0 c61c 0c clock_step +1.067923 s
14 Sep 12:19:41 ntpd[4689]: 0.0.0.0 c614 04 freq_mode
14 Sep 12:19:42 ntpd[4689]: 0.0.0.0 c618 08 no_sys_peer
14 Sep 12:22:58 ntpd[4689]: 0.0.0.0 c628 08 no_sys_peer
14 Sep 12:26:11 ntpd[4689]: 0.0.0.0 c638 08 no_sys_peer
Here are Additional outputs of ntpq -c as
and others that I am trying to understand as well.
I have been using this links to troubleshoot: http://support.ntp.org/bin/view/Support/TroubleshootingNTP https://rags.wordpress.com/2011/10/17/how-to-debug-ntp-issues/
ntpd exiting on signal 15