peer authentication and md5
The problem is still your pg_hba.conf file (/etc/postgresql/9.1/main/pg_hba.conf*).
This line:
local all postgres peer
Should be:
local all postgres md5
If you can’t find this file, running locate pg_hba.conf should show you where the file is.
After altering this file, don’t forget to restart your PostgreSQL server. If you’re on Linux, that would be sudo service postgresql restart.
These are brief descriptions of both options according to the official PostgreSQL docs on authentication methods.
Peer authentication
** The peer authentication method works by obtaining the client’s operating system user name from the kernel and using it as the allowed database user name (with optional user name mapping). This method is only supported on local connections.
Password authentication
** The password-based authentication methods are md5 and password. These methods operate similarly except for the way that the password is sent across the connection, namely MD5-hashed and clear-text respectively.
** If you are at all concerned about password “sniffing” attacks then md5 is preferred. Plain password should always be avoided if possible. However, md5 cannot be used with the db_user_namespace feature. If the connection is protected by SSL encryption then password can be used safely (though SSL certificate authentication might be a better choice if one is depending on using SSL).
Sample location for pg_hba.conf:
/etc/postgresql/9.1/main/pg_hba.conf