In my setup I have several OpenVPN clients pointing to a vpn server's dns name. let's use vpn1.mydomain.com as an example. The server's public IP pointed to by that domain would be for example 126.96.36.199
Now I change the DNS record and point the vpn1.mydomain.com domain to another IP, for example 188.8.131.52.
My question is, when is the DNS lookup performed by clients to resolve the new IP for OpenVPN, and how can I trigger a lookup to make clients use the new IP? Do I need to restart service on clients, on server or is there some way to flush dns cache and make client open new connection to new IP?
Note: I am aware that using domain names may not be considered best practices for this kind of setup, and that using the IP directly might be preferred by some.