I'm having some strange DNS issues and wondered if someone more knowledgeable than me might be able to help out.
I have a personal domain and a Spark residential account with a dynamic public IP. I use a free Cloudflare account as a dynamic DNS service to resolve vpn.mydomain.co.nz to my public IP. I run a couple of VPN servers on my home network
and update the Cloudflare DNS records every time my public IP changes, using a script on my Raspberry Pi and the Cloudflare APi.
Recently I've been noticing that quite often (but with no regular pattern), my domain is resolving to the wrong IP address. The IP address is always the same - 122.57.100.228. It's not just my personal connection that resolves incorrectly - sites like https://www.whatsmydns.net confirm that it's resolving to the wrong IP from multiple international locations. Throughout this time (a couple of weeks now), my public IP has remained constant.
I've done a bit of troubleshooting but haven't got anywhere yet.
First of all, is 122.57.100.228 an address with any significance or relevance within the Spark network? From what I can find online it's just a standard public address within Spark's pool.
There are a few things I have up my sleeve to try but would appreciate any comment on the IP address in question before I try something else...