Using Pgbouncer, Repmgr, and Keepalived To Replace Pgpool, Enabling Authentication Passthrough

We’ve been a longtime user of pgpool to provide connection pooling and high-availability for our Postgres cluster. Our setup, however, uses md5sum for authentication, which has major weaknesses:

• password guessing: Even a laptop can compute several million MD5 hashes per second
• replay attack: only 4 billion unique 4-byte salts so it’s susceptible to replay attacks.
• stolen hash: You don’t need the original password to login…