ourdiaspora <ourdiaspora@protonmail.com> writes:
> psql -d cpacweb -U cpaca
> psql: FATAL: Peer authentication failed for user "cpaca"
The reason that's able to make a connection to the PG server
is that it's not going through TCP at all, but a Unix socket.
I'd guess at this point that your configuration never worked
for TCP connections --- either localhost or not --- because
your kernel packet filter isn't permitting it. It's a gold
plated certainty that the default packet filter configuration
wouldn't allow traffic to port 5432 from off-machine. Whether
it would allow such traffic from localhost is less certain,
but the symptoms you're showing sure look like yours doesn't.
Saying you haven't touched that configuration doesn't excuse
you from investigating it.
regards, tom lane