NTP local query always times out

On RHEL / CentOS 6 and 7, for whatever reason ntpq tries to query the IPv6 loopback at ::1 instead of the IPv4 loopback at 127.0.0.1. With this in mind, I added this line to my /etc/ntp.conf file:

restrict ::1

Saved the file then restarted ntpd

service ntpd restart

now the command:

ntpq -p

works as expected. (This is the same as running ntpq in command-line mode and then issuing the peers command.)

I prefer this solution since you do not have to enable communications with ntpd via a potentially public Ethernet interface, which may be a security concern.

I was expecting ntpq to query local server via 127.0.0.1, but it turns out to be querying local server via ethernet network interface.

Although I have no idea why a local ntp query would have to go through ethernet, but in configuration file I added

restrict <eht0 ip address>

And now NTP works fine.