This weekend I replaced my ten year old Xeon based Stratum 1 server with a Stratum 1 server based on the Raspberry Pi. I am very happy with the power usage going back from 89 Watt to just a few Watt The reference clock didn’t change: it is still the original Garmin 18LVC GPS. I used chronyd instead of ntpd because it was pre-installed in the Linux image I used. The image is the Centos 7 ARM image BTW, not the more common Raspbian image because all my Linux servers are Centos based and I like to use the same tools and configuration on all servers independent on the underlying hardware.
On IPv4 there is just a small dent in the graph as you can see at https://www.ntppool.org/scores/22.214.171.124
As the new server supports IPv6, I also wanted to add this address to the pool. When adding the server domain name ntp4.ipv6.linocomm.net to the pool, the system however responds with the message “Could not check NTP status”.
I can access the NTP server over IPv6 from my other servers in the field, so basic connectivity doesn’t seem to be a problem. But so many things changed with the move from the old to the new server that it is somewhat difficult to track down the issue.
Any hints where I should start to debug this issue?