I'm trying to configure two NTP servers to be peers to each other but I have no idea how to tell if it is working or not or whether my NTP configuration is even correct. I've put a simplified view of how my NTP servers are configured below.Server A :   ntp.conf :     restrict default kod nomodify notrap noquery    peer Server BServer B :  ntp.conf :     restrict default kod nomodify notrap noquery    peer Server AI have two questions with regards to this setup:EDIT : Added clarification to question 1Using the simplified ntp.conf I have put up, will the two NTP servers act as peers to each other by attempting to correct their time? I am looking for the simplest possible setup for ntp peers and I am not sure whether I am configuring it correctly. How do I confirm that my NTP peer configuration is working?The reason I'm asking the above questions is because I have an alternative setup where the only change is that I've re-added the nopeer setting to the restrict stanza and in both cases the following output is returned:Server A:  ntpdc -l    sym_active : Server BServer B:  ntpdc -l    sym_active : Server AWhich makes no sense whatsoever since the nopeer directive should not enable me to peer the two servers together. Note : This is run on CentOS 6EDIT : Actual ntp.conf files and ntpq -p as requested. I am not sure how useful these would be:Server A:  driftfile /var/lib/ntp/drift  restrict default kod nomodify notrap noquery  restrict -6 default kod nomodify notrap noquery  restrict 127.0.0.1   restrict -6 ::1   peer 192.168.122.3Server B:  driftfile /var/lib/ntp/drift  restrict default kod nomodify notrap noquery  restrict -6 default kod nomodify notrap noquery  restrict 127.0.0.1  restrict -6 ::1  peer 192.168.122.2The output of ntpq -p after more than 5 minutes (which exceeds the poll interval) is the following for each server.Server A:     remote           refid      st t when poll reach   delay   offset  jitter============================================================================== secure.jzhu.loc .INIT.          16 u   55   64    0    0.000    0.000   0.000Server B:     remote           refid      st t when poll reach   delay   offset  jitter============================================================================== masterdns.jzhu. .INIT.          16 u   33   64    0    0.000    0.000   0.000Note : With or without the nopeer directive, the reach remains consistently at 0. Although that's more likely due to the fact that they are both stratum 16 servers than anything else.Note : iptables -F was run when performing this test and the default policy for the chain INPUT was ACCEPT. 
Properly configuring symmetric active NTP?
centos;ntp