Would it make sense to use a dynamic DNS service? about pi-hole-on-google-compute-engine-free-tier-with-full-tunnel-and-split-tunnel-wireguard-vpn-configs HOT 1 CLOSED

I think it's better to use a static IP, always. On Google Compute Engine a static IP does not cost you anything, it is part of the Free Tier if you provision one on their Premium Network. That said, not everyone is running this on Google Cloud - so I'm thinking out loud:

If your server is directly being assigned a public IP address, you can fetch the public IP on demand with this command. There is no network traffic associated with running this command:

ip addr show dev $(ip -4 route ls | grep default | grep -Po '(?<=dev )(\S+)' | head -1) scope global | awk '/inet / {split($
2,var,"/"); print var[1]}'

If you are behind a DHCP server, such as a router in your home, or in Google Compute Engine, you will not get your public IP address with the command above. You would instead see the IP address served by your DHCP server. I think the quickest way to get your public IP address is by probing a DNS server:

dig TXT +short o-o.myaddr.l.google.com @ns1.google.com | awk -F'"' '{ print $2}'

You could store the output of the dig command into a text file or environment variable, and compare the subsequent outputs against the contents of the file. When a change is detected, you could trigger your dynamic DNS software to update the DNS record of a domain you own.

Because DNS updates take time to propagate, when you have an opportunity to use a static IP for your VPN server, you should.

from pi-hole-on-google-compute-engine-free-tier-with-full-tunnel-and-split-tunnel-wireguard-vpn-configs.