What do they use for a timebase?
-----Original Message-----
From: Ken Hohhof
Sent: Monday, October 10, 2016 9:40 AM
To: af@afmug.com
Subject: Re: [AFMUG] Update on DHCP - Calix failures
If you have Cisco core routers in your network, I have found them to be good
NTP servers. Set them up with however many masters you want, there are nice
ACL commands to limit clients and prevent amplification attacks. Should
probably specify them by loopback address to insure they are reachable even
if OSPF reconfigures path to router.
-----Original Message-----
From: Af [mailto:af-boun...@afmug.com] On Behalf Of Chuck McCown
Sent: Monday, October 10, 2016 10:21 AM
To: af@afmug.com
Subject: Re: [AFMUG] Update on DHCP - Calix failures
Nice clock source. Thanks.
I think I am going to buy the larger one. It has an onboard OCXO for
holdover timing.
-----Original Message-----
From: Seth Mattinen
Sent: Monday, October 10, 2016 8:55 AM
To: af@afmug.com
Subject: Re: [AFMUG] Update on DHCP - Calix failures
On 10/10/16 7:32 AM, Chuck McCown wrote:
I am guessing that Xmission was giving us a malformed or otherwise
unpalatable NTP time hack. Calix reacted by setting the RTC to goofy
time. I have never dug into the internals of NTP. I guess the next
step would be to wireshark that and figure out what is going on. But
Calix should fall back to secondary NTP or freerun if it does not like
what it is getting. And give an alarm.
How many tickers were configured? Good practice is to configure at least
4 from different sources so that NTP can detect a false ticker or bad time
source. Configuring two is bad. If you only have the option to configure one
or two NTP servers then only do one but sourcing off a time server that has
at least four. NTP doesn't do "primary" or "secondary".
These are cheap to have your own GPS clock: https://www.css-timemachines.com
~Seth
