I am confused about authentication. I understand that in the local connection case, I have choices of “peer”, and “md5” (password).
In pg_hba.conf, I have the lines:
local all all peer
local all all md5
I have an OS user “postgres”, and I can “su – postgres”, which brings me to a shell and I can invoke psql successfully.
I believe that, as root, I should be able to “psql -U postgres -W” and logon with a password. I can’t. When I try, I get:
psql: error: connection to server on socket "/var/run/postgresql/.s.PGSQL.5432" failed: FATAL: Peer authentication failed for user "postgres"
Notice I am failing “peer” authentication. Seems to me that if I explicitly ask for a password, “-W”, I should be using “md5” authentication.
Can anybody straighten me out?