Hi List I have ntp running as a service on a PC, with the expectation that it would keep time in synch to my ntp server. However, while I can manually update the time using "ntpdate -u ...", I find that if I manually force the wrong time, the ntpd service does not automatically re-synch the system time with the ntp server: - Current time: [admin@lol ~]# date Wed Jan 27 10:54:21 AST 2016 - Force wrong time: [admin@lol ~]# date -s 09:29 Wed Jan 27 09:29:00 AST 2016 - Restart ntp service: [admin@lol ~]# service ntpd restart Shutting down ntpd: [ OK ] Starting ntpd: [ OK ] - Time not synched (even after about 10 minutes) [admin@lol ~]# date Wed Jan 27 09:35:52 AST 2016 - use ntpdate -u to force synch: [admin@lol ~]# ntpdate -u time.lol.com 27 Jan 11:02:28 ntpdate[18570]: step time server 172.16.100.13 offset 5154.859809 sec [osadmin@test-till ~]# [admin@lol ~]# date Wed Jan 27 11:03:09 AST 2016 I'm not sure if this is a configuration issue with ntp (ntp.conf looks fine, as well as /etc/sysconfig/ntpd.conf (pasted below). /etc/ntp.conf: restrict default nomodify notrap nopeer noquery restrict 127.0.0.1 restrict ::1 server time.lol.com driftfile /var/lib/ntp/drift /etc/sysconfig/ntpd" # Drop root to id 'ntp:ntp' by default. OPTIONS="-x -u ntp:ntp -p /var/run/ntpd.pid" # Set to 'yes' to sync hw clock after successful ntpdate SYNC_HWCLOCK=yes # Additional options for ntpdate NTPDATE_OPTIONS="" --- Here are some diagnostic queries with ntpq: --- [admin@lol ~]# ntpq -pcrv remote refid st t when poll reach delay offset jitter ============================================================================== 10.1.0.111 xxx.xx.xx.x 2 u 26 64 1 3.618 6018473 0.001 associd=0 status=c012 leap_alarm, sync_unspec, 1 event, freq_set, version="ntpd 4.2.6p5@1.2349-o Sat Nov 23 18:20:11 UTC 2013 (1)", processor="i686", system="Linux/2.6.32-504.1.3.el6.i686", leap=11, stratum=16, precision=-20, rootdelay=0.000, rootdisp=0.405, refid=INIT, reftime=00000000.00000000 Thu, Feb 7 2036 9:28:16.000, clock=da52e461.90fabbc4 Wed, Jan 27 2016 9:38:25.566, peer=0, tc=3, mintc=3, offset=0.000, frequency=356.208, sys_jitter=0.000, clk_jitter=0.001, clk_wander=0.000 ---- What could be the issue? Any help would be appreciated. Here is the output from running the ntpd service in debug mode: --- [admin@lol ~]# ntpd -d ntpd 4.2.6p5@1.2349-o Sat Nov 23 18:20:11 UTC 2013 (1) 27 Jan 09:29:58 ntpd[18652]: proto: precision = 0.931 usec 27 Jan 09:29:58 ntpd[18652]: 0.0.0.0 c01d 0d kern kernel time sync enabled event at 0 0.0.0.0 c01d 0d kern kernel time sync enabled Finished Parsing!! 27 Jan 09:29:58 ntpd[18652]: ntp_io: estimated max descriptors: 1024, initial socket boundary: 16 27 Jan 09:29:58 ntpd[18652]: Listen and drop on 0 v4wildcard 0.0.0.0 UDP 123 27 Jan 09:29:58 ntpd[18652]: Listen and drop on 1 v6wildcard :: UDP 123 27 Jan 09:29:58 ntpd[18652]: Listen normally on 2 lo 127.0.0.1 UDP 123 restrict: op 1 addr 127.0.0.1 mask 255.255.255.255 mflags 00003000 flags 00000001 27 Jan 09:29:58 ntpd[18652]: Listen normally on 3 eth 172.16.0.213 UDP 123 restrict: op 1 addr 172.16.0.213 mask 255.255.255.255 mflags 00003000 flags 00000001 27 Jan 09:29:58 ntpd[18652]: Listen normally on 4 lo ::1 UDP 123 restrict: op 1 addr ::1 mask ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff mflags 00003000 flags 00000001 27 Jan 09:29:58 ntpd[18652]: Listen normally on 5 eth fe80::3640:b5ff:fe90:104e UDP 123 restrict: op 1 addr fe80::3640:b5ff:fe90:104e mask ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff mflags 00003000 flags 00000001 27 Jan 09:29:58 ntpd[18652]: peers refreshed 27 Jan 09:29:58 ntpd[18652]: Listening on routing socket on fd #22 for interface updates restrict: op 1 addr 0.0.0.0 mask 0.0.0.0 mflags 00000000 flags 000001d0 restrict: op 1 addr :: mask 0.0.0.0 mflags 00000000 flags 000001d0 restrict: op 1 addr 127.0.0.1 mask 255.255.255.255 mflags 00000000 flags 00000000 restrict: op 1 addr ::1 mask ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff mflags 00000000 flags 00000000 key_expire: at 0 associd 17148 peer_clear: at 0 next 1 associd 17148 refid INIT event at 0 10.1.0.111 8011 81 mobilize assoc 17148 newpeer: 172.16.0.213->10.1.0.111 mode 3 vers 4 poll 6 10 flags 0x1 0x1 ttl 0 key 00000000 27 Jan 09:29:58 ntpd[18652]: 0.0.0.0 c016 06 restart event at 0 0.0.0.0 c016 06 restart 27 Jan 09:29:58 ntpd[18652]: 0.0.0.0 c012 02 freq_set kernel 356.208 PPM event at 0 0.0.0.0 c012 02 freq_set kernel 356.208 PPM transmit: at 1 172.16.0.213->10.1.0.111 mode 3 len 48 auth_agekeys: at 1 keys 1 expired 0 receive: at 1 172.16.0.213<-10.1.0.111 mode 4 len 48 event at 1 10.1.0.111 8024 84 reachable clock_filter: n 1 off 6018.651057 del 0.003849 dsp 7.945313 jit 0.000001 . . --- I'm tempted to stick an "ntpdate -u ..." in the crontab to force time-synch, but I don't see why that's needed if ntpd service should already be fulfilling that purpose. Many thanks in advance, Traiano _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx https://lists.centos.org/mailman/listinfo/centos