[c-nsp] c877 and ntp oddness

[David Freedman]

Well, 

1. the problem is apparent in both 15T and 22T
2. No access groups are configured
3. NTPv3, 2 and 1 were tried.
4. Peer syncs and after about 10 mins is declared "insane" and relationship is lost,
removal of the "clock-period" (in 15T) fixes the issue which points to incorrect calculation
of the clock-period (hardware offset), since this persists between versions
would suggest a hardware issue to me?

Dave.

------------------------------------------------
David Freedman
Group Network Engineering 
Claranet Limited
http://www.clara.net



-----Original Message-----
From: Kevin Graham [mailto:kgraham at industrial-marshmallow.com]
Sent: Sun 7/19/2009 04:24
To: David Freedman; cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] c877 and ntp oddness
 

> >> Have a bizarre NTP issue with 877 routers running 12.4(T) train.

> >>
> >> - Only seems to affect a small percentage of 877 routers,
> >> 878s, 1800s , 2800s seem to be fine
> > 
> > A coworker reported the exact same behavior a couple of weeks ago. They
> > got 87x routers with a new hardware revision, these routers do not sync
> > with ntp anymore. TAC case is open, but nothing concrete so far.

Are you sure its hardware related and release-specific? With the
introduction of NTPv4 in (22)T it appears NTP access-groups are broken,
requiring them to be removed or everything given 'peer' access. (Covered in
CSCsw79186, though the problem is much more widespread than release notes
there indicate).