Problems with PostgreSQL client apps

Hi all. I've recently been given a laptop running Redhat 8.0 by my work, and I'm having trouble getting PostgreSQL running. PostgreSQL starts when the laptop boots, but I can't access any of the PostgreSQL client applications such as psql, createuser, createdb, etc.

Here's what happens. These errors occur for both root and the other user on the machine, pablo.

If I try to access the psql interactive terminal:

[root@argon root]$ psql
psql: FATAL 1: Database "root" does not exist in the system catalog.

If I try to create a database for user unbc:

[root@argon root]$ createdb -U unbc -W unbc
Password:
psql: FATAL 1: IDENT authentication failed for user "unbc"

createdb: database creation failed.

So then I try to create the user unbc:

[root@argon root]$ createuser -a -d -e -P unbc
Enter password for user "unbc":
Enter it again:
psql: FATAL 1: user "root" does not exist.
createuser: creation of user "unbc" failed.

If I try to create a database unbc, with no user but a password:

[root@argon root]$ createdb -W unbc
Password:
psql FATAL 1: user "root" does not exist.
createdb: database creation failed.

Can anyone give any advice as to what the problem is?

Thanks in advance,
Pablo

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