Accessing servers through hostname now requires FQDN?

After upgrading to Linux Mint 20, the servers (pgsql databases and windows network share) on our internal network now require the fully qualified domain instead of just the machine name.

For example, I used to be able to connect through simply px-data01-d but now need px-data01-d.dpsnetwork.org.

This is a huge headache as we have hundreds of projects that referenced the hostname, not the FQDN.

Nothing has changed on the network, and my Windows machine is still using the hostname.

Our former database administrator who uses Linux mentioned at one point a way of telling your machine to search differently for how it accesses servers on the network, and I see there is the /etc/hosts file as well, but I don’t know if that is the right approach.