NTP server x.x.x.x prefer
In the network where I am currently working we have configured the following:
ntp server x.x.x.x prefer
ntp server y.y.y.y
I thought the prefer keyword made us choose the configured server as the time source.
The y.y.y.y server is a GPS clock (stratum 1) and the x.x.x.x server is a 2811 router (stratum 2). The local router (the ntp client) will only synchronize with the superior stratum device regardless of the prefer keyword. Is this normal behaviour.
Also, I know that this is a strange thing to do but it was an interesting result that I wasn't expecting.
Does the prefer keyword only work if the sources have an equal stratum and one of the sources is not a GPS clock? I tried labbing this by configuring my 2811 router that is an NTP server as a stratum 1. The local NTP client still chose the GPS source even with the prefer keyword pointed to the 2811. (The GPS clock had a "ref clock" of .GPS. instead of an IP address and the stratums were the same)