[CentOS] Date drift and ntpd

[Jason Pyeron]

> -----Original Message-----
> From: centos-bounces at centos.org 
> [mailto:centos-bounces at centos.org] On Behalf Of Simon Billis
> Sent: Thursday, August 12, 2010 8:14
> To: 'CentOS mailing list'
> Subject: Re: [CentOS] Date drift and ntpd
> 
> Hi,
> 
> > > Jason Pyeron sent a missive on 2010-08-12:
> > >
> > > > We have a local time server and all of our machines are
> > > pointed at it
> > > > for the time.
> > > >
> > > > How can the clock drift by a day and a half?
> > > >
> > > > [root at devserver21 ~]# date
> > > > Fri Aug 13 14:43:29 EDT 2010
> > > > [root at devserver21 ~]# rdate -s 192.168.1.67
> > > > [root at devserver21 ~]# date
> > > > Thu Aug 12 07:02:39 EDT 2010
> > > > [root at devserver21 ~]# cat /etc/ntp.conf | grep -v ^# | 
> grep -v ^$ 
> > > > restrict default nomodify notrap noquery restrict 
> 127.0.0.1 server
> > > > 192.168.1.67 server 192.168.1.66 server 192.168.1.65
> > > > server  127.127.1.0     # local clock
> > > > fudge   127.127.1.0 stratum 10
> > > > driftfile /var/lib/ntp/drift
> > > > broadcastdelay  0.008
> > > > keys            /etc/ntp/keys
> > > >
> > > >
> > >
> > > Hi,
> > >
> > > It is unlikely that the machine in question drifted 
> forward in time 
> > > if ntpd was running. Have a look at the logs /var/log/messages it 
> > > should contain the ntpd log messages
> > 
> > [root at devserver21 ~]# grep ntpd /var/log/messages </snip>
> /SNIP
> > Jul 29 17:47:24 devserver21 ntpd[3475]: synchronized to LOCAL(0), 
> > stratum 10 Aug 12 22:48:29 devserver21 ntpd[3475]: 
> > sendto(192.168.1.66): Operation not permitted
> > [root at devserver21 ~]# uptime
> >  08:10:19 up 164 days,  9:56,  2 users,  load average: 0.20, 0.54, 
> > 0.81
> > [root at devserver21 ~]#
> 
> What happened between July 29 and now? Is there nothing in 
> the logs for that period?
> 

Nothing of note, I do have full logs from those days...
[root at devserver21 ~]# grep ' 00:00:.. devserver21 arpwatch: bogon 192.168.1.67
0:30:67:0:cf:fd' /var/log/messages
Jul 26 00:00:37 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Jul 27 00:00:47 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Jul 28 00:00:44 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Jul 29 00:00:41 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Jul 30 00:00:08 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Jul 31 00:00:08 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  1 00:00:14 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  2 00:00:22 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  3 00:00:11 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  4 00:00:58 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  5 00:00:06 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  6 00:00:06 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  7 00:00:03 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  8 00:00:43 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug  9 00:00:16 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug 10 00:00:08 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug 11 00:00:34 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug 12 00:00:19 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
Aug 13 00:00:20 devserver21 arpwatch: bogon 192.168.1.67 0:30:67:0:cf:fd
[root at devserver21 ~]#

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