Am I @localhost or @computer-5?

Question

Why is bash shell sometimes saying I'm at @localhost while other times it says I'm at @computer-5?

Answer 1

Some DHCP servers (and clients) are configured to assign a hostname just like an IP address. In these cases the computer's hostname does in fact change to e. g. computer-5 (until it gets a lease assigning a different name, or the lease is relinquished). localhost will still work for the loopback interface, but the DHCP-assigned hostname will (or should) resolve to the DHCP-assigned address specifically.