Multiple VPS

I have 2 vps servers and each have one ip address. I was wondering if it is possible to use one domain so that vps1.mydomain.com is the hostname to one vps and vps2.mydomain.com is hostname for the 2nd vps?

My domain is registered at godaddy and currently I have mydomain.com hostname set to ns1 and ns2 of the ip of my vps1 server as well as nameservers set to ns1 and ns2.mydomain.com.

Now I plan to get a 2nd server which will be on a different ip and would like to be able to use the same domain.

Is this possible or do I need to use another domain?

for hostname, you need to use subdomain and not domain so yes that is te correct setup and you can have an unlimited number of servers with one domain.

You only need to define at your dns A records for each subdomain.