service ntpd restart fails

ramseyrt · 04-21-2013, 10:27 AM

Hello,

I have a system that reports an ntpd failure during a "service ntpd restart". It seems like everything should be working (of course). Here's the data:

Code:

[root@RHEL_Server ~]# service ntpd restart

Shutting down ntpd:                                        [  OK  ]
ntpd: Synchronizing with time server:                      [FAILED]
Starting ntpd:                                             [  OK  ]

The error messages read:

Code:

[root@RHEL_Server ~]# tail /var/log/messages| grep ntpd

Apr 21 14:11:19 RHEL_Server ntpd[1113]: ntpd exiting on signal 15
Apr 21 14:11:19 RHEL_Server ntpdate[1303]: no server suitable for synchronization found
Apr 21 14:11:19 RHEL_Server ntpd[1306]: ntpd 4.2.2p1@1.1570-o Thu Nov 26 11:35:07 UTC 2009 (1)
Apr 21 14:11:19 RHEL_Server ntpd[1307]: precision = 1.000 usec
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface wildcard, 0.0.0.0#123 Disabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface wildcard, ::#123 Disabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface lo, ::1#123 Enabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface eth0, fe80::1aa9:5ff:fe3c:b7a6#123 Enabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface eth1, fe80::1aa9:5ff:fe3c:374a#123 Enabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface lo, 127.0.0.1#123 Enabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface eth0, 192.168.6.6#123 Enabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: Listening on interface eth1, 10.6.0.4#123 Enabled
Apr 21 14:11:19 RHEL_Server ntpd[1307]: kernel time sync status 0040
Apr 21 14:11:19 RHEL_Server ntpd[1307]: frequency initialized 21.183 PPM from /var/lib/ntp/drift

My ntp.conf file looks similar to other working ntp.conf files on RHEL boxes on my network:

Code:

[root@RHEL_Server ~]# grep -v ^# /etc/ntp.conf

restrict default kod nomodify notrap nopeer noquery
restrict 127.0.0.1 
restrict -6 ::1
fudge   127.127.1.0 stratum 10
driftfile /var/lib/ntp/drift
keys /etc/ntp/keys
server 192.168.6.15
restrict 192.168.6.15 mask 255.255.255.255 nomodify notrap noquery

The service looks good in chkconfig (default runlevel is 5)

Code:

[root@RHEL_Server ~]# chkconfig --list | grep ^ntpd

ntpd            0:off   1:off   2:off   3:on    4:off   5:on    6:off

I'm not running any kind of firewall (closed network)

Code:

[root@RHEL_Server ~]# chkconfig --list | grep ^iptables

iptables        0:off   1:off   2:off   3:off   4:off   5:off   6:off

[root@RHEL_Server ~]# iptables --list

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

I can talk to the time server

Code:

[root@RHEL_Server ~]# ntpdate -d 192.168.6.15

21 Apr 14:12:14 ntpdate[1377]: ntpdate 4.2.2p1@1.1570-o Thu Nov 26 11:35:07 UTC 2009 (1)
Looking for host 192.168.6.15 and service ntp
host found : Cisco_Router
transmit(192.168.6.15)
receive(192.168.6.15)
transmit(192.168.6.15)
receive(192.168.6.15)
transmit(192.168.6.15)
receive(192.168.6.15)
transmit(192.168.6.15)
receive(192.168.6.15)
transmit(192.168.6.15)
server 192.168.6.15, port 123
stratum 3, precision -32, leap 00, trust 000
refid [192.168.6.15], delay 1.02580, dispersion 0.00000
transmitted 4, in filter 4
reference time:    d51e7100.b0fa7b0a  Sun, Apr 21 2013 14:06:56.691
originate timestamp: d51e7238.45614c17  Sun, Apr 21 2013 14:12:08.271
transmit timestamp:  d51e723e.c3b5286b  Sun, Apr 21 2013 14:12:14.764
filter delay:  1.02585  1.02582  1.02580  1.02580 
         0.00000  0.00000  0.00000  0.00000 
filter offset: -6.49356 -6.49357 -6.49357 -6.49357
         0.000000 0.000000 0.000000 0.000000
delay 1.02580, dispersion 0.00000
offset -6.493570

21 Apr 14:12:14 ntpdate[1377]: step time server 192.168.6.15 offset -6.493570 sec

It even looks like NTP might be running

Code:

[root@RHEL_Server ~]# ntpdc -p
     remote           local      st poll reach  delay   offset    disp
=======================================================================
=  Cisco_Router  192.168.6.6      3   64   77 0.00023 -6.492943 1.08420

Quote:

The character in the left margin indicates the mode this peer entry is operating in. A + denotes symmetric active, a - indicates symmetric passive, a = means the remote server is being polled in client mode, a ^ indicates that the server is broadcasting to this address, a ~ denotes that the remote peer is sending broadcasts and a * marks the peer the server is currently synchronizing to.

http://doc.ntp.org/4.1.1/ntpdc.htm

I know the NTP server, a Cisco 3945, is serving NTP properly because other devices are properly slaved to it.

Any ideas?

Thanks in advance,

Rob

roger_heslop · 04-22-2013, 03:13 AM

I can't remember if this affects NTP on Linux specifically, but I've seen cases where a client wouldn't sync with a time server if the time were too far off, greater than 4 or 5 minutes for example.

Can you manually set your time to be no more than a few minutes off and double check?

ramseyrt · 04-23-2013, 07:25 AM

Hello,

I performed a quick 'while true;do;date;sleep 1;done' loop while typing "show date" on my NTP server (Cisco router). The RHEL system and router are within 10 seconds of each other.

Any other ideas?

Thanks in advance,

Rob