NTP time synchronization failed
[root@server1 ~]# /etc/init.d/ntpd status
ntpd (pid 32243) is running...
[root@server1 ~]# chkconfig --list ntpd
ntpd 0:off 1:off 2:on 3:on 4:on 5:on 6:off
[root@server1 ~]# ntpdc
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 30
watchdog timer: 13 s
ntpdc> exit
System peer seems to be local ntp didnot sync with the ntp server.
[root@server1 ~]# ntpdc -c sysinfo
system peer: LOCAL(0)
system peer mode: client
leap indicator: 00
stratum: 11
precision: -20
root distance: 0.00000 s
root dispersion: 0.01141 s
reference ID: [127.127.1.0]
reference time: d563fabb.55ff4a47 Thu, Jun 13 2013 9:00:59.335
system flags: auth monitor ntp kernel stats
jitter: 0.000000 s
stability: 0.000 ppm
broadcastdelay: 0.003998 s
authdelay: 0.000000 s
[root@server1 ~]# grep server /etc/ntp.conf
# Use public servers from the pool.ntp.org project.
#server 0.centos.pool.ntp.org
#server 1.centos.pool.ntp.org
#server 2.centos.pool.ntp.org
server 107.22.5.68
#broadcast 192.168.1.255 key 42 # broadcast server
#broadcast 224.0.1.1 key 42 # multicast server
#manycastserver 239.255.254.254 # manycast server
server 127.127.1.0 # local clock
Edit the configuration file and change the contents like below
[root@server1 ~]# vi /etc/ntp.conf
You have new mail in /var/spool/mail/root
[root@server1 ~]# grep server /etc/ntp.conf
# Use public servers from the pool.ntp.org project.
server 0.centos.pool.ntp.org
server 1.centos.pool.ntp.org
server 2.centos.pool.ntp.org
#server 107.22.5.68
#broadcast 192.168.1.255 key 42 # broadcast server
#broadcast 224.0.1.1 key 42 # multicast server
#manycastserver 239.255.254.254 # manycast server
server 127.127.1.0 # local clock
[root@server1 ~]# /etc/init.d/ntpd restart
Shutting down ntpd: [ OK ]
Starting ntpd: [ OK ]
[root@server1 ~]# ntpdate -u pool.ntp.org
13 Jun 09:05:34 ntpdate[20593]: adjust time server 128.113.28.67 offset -0.089041 sec
[root@server1 ~]# ntpdate -b pool.ntp.org
13 Jun 09:05:42 ntpdate[20600]: the NTP socket is in use, exiting
Synced only to the LOCAL
[root@server1 ~]# grep ntp /var/log/messages
Jun 13 09:06:03 server1 ntpd[20516]: synchronized to LOCAL(0), stratum 10
Jun 13 09:06:03 server1 ntpd[20516]: kernel time sync enabled 0001
[root@server1 ~]#
[root@server1 ~]# ntpdc
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 37 s
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 42 s
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 45 s
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 46 s
ntpdc> exit
Check the port 123 is opened . Since port 123 is a UDP , you can check it with nc command.
nc -zu destination ip 123
Here the * shows , it is now synced to the ntp server
[root@server1 ~]# ntpq
ntpq> pe
remote refid st t when poll reach delay offset jitter
==============================================================================
lasvegas-nv-dat 72.8.140.240 3 u 11h 1024 0 140.810 -1.350 0.000
38.117.195.101 .STEP. 16 u 505d 1024 0 0.000 0.000 0.000
*bindcat.fhsu.ed 128.138.140.44 2 u 361 1024 377 107.537 0.016 0.296
LOCAL(0) .LOCL. 10 l 1 64 377 0.000 0.000 0.001
ntpq> as
ind assID status conf reach auth condition last_event cnt
===========================================================
1 25892 8053 yes yes none reject lost reach 5
2 25893 8063 yes yes none reject lost reach 6
3 25894 96f4 yes yes none sys.peer reachable 15
4 25895 9044 yes yes none reject reachable 4
ntpq> rv
assID=0 status=06f4 leap_none, sync_ntp, 15 events, event_peer/strat_chg,
version="ntpd 4.2.2p1@1.1570-o Sat Dec 19 00:56:13 UTC 2009 (1)",
processor="x86_64", system="Linux/2.6.18-238.19.1.el5", leap=00,
stratum=3, precision=-20, rootdelay=131.707, rootdispersion=39.163,
peer=25894, refid=25.201.113.150,
reftime=d5814694.df62076d Fri, Jul 5 2013 14:20:20.872, poll=10,
clock=d581480a.30d80bc0 Fri, Jul 5 2013 14:26:34.190, state=4,
offset=0.016, frequency=-50.345, jitter=0.296, noise=0.309,
stability=0.001, tai=0
Check the status of it using the below command.
[root@ server1~]# ntpstat
synchronised to NTP server (25.201.113.150) at stratum 3
time correct to within 39 ms
polling server every 1024 s
Now it is synced to the ntp server.
[root@server1 ~]# /etc/init.d/ntpd status
ntpd (pid 32243) is running...
[root@server1 ~]# chkconfig --list ntpd
ntpd 0:off 1:off 2:on 3:on 4:on 5:on 6:off
[root@server1 ~]# ntpdc
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 30
watchdog timer: 13 s
ntpdc> exit
System peer seems to be local ntp didnot sync with the ntp server.
[root@server1 ~]# ntpdc -c sysinfo
system peer: LOCAL(0)
system peer mode: client
leap indicator: 00
stratum: 11
precision: -20
root distance: 0.00000 s
root dispersion: 0.01141 s
reference ID: [127.127.1.0]
reference time: d563fabb.55ff4a47 Thu, Jun 13 2013 9:00:59.335
system flags: auth monitor ntp kernel stats
jitter: 0.000000 s
stability: 0.000 ppm
broadcastdelay: 0.003998 s
authdelay: 0.000000 s
[root@server1 ~]# grep server /etc/ntp.conf
# Use public servers from the pool.ntp.org project.
#server 0.centos.pool.ntp.org
#server 1.centos.pool.ntp.org
#server 2.centos.pool.ntp.org
server 107.22.5.68
#broadcast 192.168.1.255 key 42 # broadcast server
#broadcast 224.0.1.1 key 42 # multicast server
#manycastserver 239.255.254.254 # manycast server
server 127.127.1.0 # local clock
Edit the configuration file and change the contents like below
[root@server1 ~]# vi /etc/ntp.conf
You have new mail in /var/spool/mail/root
[root@server1 ~]# grep server /etc/ntp.conf
# Use public servers from the pool.ntp.org project.
server 0.centos.pool.ntp.org
server 1.centos.pool.ntp.org
server 2.centos.pool.ntp.org
#server 107.22.5.68
#broadcast 192.168.1.255 key 42 # broadcast server
#broadcast 224.0.1.1 key 42 # multicast server
#manycastserver 239.255.254.254 # manycast server
server 127.127.1.0 # local clock
[root@server1 ~]# /etc/init.d/ntpd restart
Shutting down ntpd: [ OK ]
Starting ntpd: [ OK ]
[root@server1 ~]# ntpdate -u pool.ntp.org
13 Jun 09:05:34 ntpdate[20593]: adjust time server 128.113.28.67 offset -0.089041 sec
[root@server1 ~]# ntpdate -b pool.ntp.org
13 Jun 09:05:42 ntpdate[20600]: the NTP socket is in use, exiting
Synced only to the LOCAL
[root@server1 ~]# grep ntp /var/log/messages
Jun 13 09:06:03 server1 ntpd[20516]: synchronized to LOCAL(0), stratum 10
Jun 13 09:06:03 server1 ntpd[20516]: kernel time sync enabled 0001
[root@server1 ~]#
[root@server1 ~]# ntpdc
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 37 s
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 42 s
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 45 s
ntpdc> loopinfo
offset: 0.000000 s
frequency: -497.501 ppm
poll adjust: 6
watchdog timer: 46 s
ntpdc> exit
Check the port 123 is opened . Since port 123 is a UDP , you can check it with nc command.
nc -zu destination ip 123
Here the * shows , it is now synced to the ntp server
[root@server1 ~]# ntpq
ntpq> pe
remote refid st t when poll reach delay offset jitter
==============================================================================
lasvegas-nv-dat 72.8.140.240 3 u 11h 1024 0 140.810 -1.350 0.000
38.117.195.101 .STEP. 16 u 505d 1024 0 0.000 0.000 0.000
*bindcat.fhsu.ed 128.138.140.44 2 u 361 1024 377 107.537 0.016 0.296
LOCAL(0) .LOCL. 10 l 1 64 377 0.000 0.000 0.001
ntpq> as
ind assID status conf reach auth condition last_event cnt
===========================================================
1 25892 8053 yes yes none reject lost reach 5
2 25893 8063 yes yes none reject lost reach 6
3 25894 96f4 yes yes none sys.peer reachable 15
4 25895 9044 yes yes none reject reachable 4
ntpq> rv
assID=0 status=06f4 leap_none, sync_ntp, 15 events, event_peer/strat_chg,
version="ntpd 4.2.2p1@1.1570-o Sat Dec 19 00:56:13 UTC 2009 (1)",
processor="x86_64", system="Linux/2.6.18-238.19.1.el5", leap=00,
stratum=3, precision=-20, rootdelay=131.707, rootdispersion=39.163,
peer=25894, refid=25.201.113.150,
reftime=d5814694.df62076d Fri, Jul 5 2013 14:20:20.872, poll=10,
clock=d581480a.30d80bc0 Fri, Jul 5 2013 14:26:34.190, state=4,
offset=0.016, frequency=-50.345, jitter=0.296, noise=0.309,
stability=0.001, tai=0
Check the status of it using the below command.
[root@ server1~]# ntpstat
synchronised to NTP server (25.201.113.150) at stratum 3
time correct to within 39 ms
polling server every 1024 s
Now it is synced to the ntp server.
