LOG: could not bind IPv4 address "0.0.0.0": Address already in use — Is another postmaster already running on port 5432?
Another process (often a second PostgreSQL install or a container) already listens on 5432.
Exact message you may see
could not bind IPv4 addressIs another postmaster already running on port 5432
Seen on:
PostgreSQL
Meaning
Homebrew + Postgres.app + Docker on the same machine commonly fight over 5432.
Common causes
- Another PostgreSQL installation running
- Docker container publishing 5432
- Stale process
⚡ Quick fix
- Find the owner: lsof -i :5432
- Stop the other instance or change the port
Detailed fix by platform
Linux
sudo lsof -i :5432
How to diagnose
- Owner — Which process holds 5432?
- Recent change — Did it start after a deploy, upgrade, or configuration change? Compare with the last working version.
🔧 Still not fixed?
Many errors look alike. If the steps above didn’t solve it, one of these is probably what you’re facing:
Similar errors
Most viewed in PostgreSQL
- could not connect PostgreSQL: could not connect to server / connection refused — Is the server running on host and accepting TCP/IP connections?
- pg_restore text dump pg_restore: error: input file appears to be a text format dump. Please use psql.
- 25P02 ERROR: current transaction is aborted, commands ignored until end of transaction block
Other ways to find it
Where this error sits
Origin: Data. Errors that are often confused with or caused by this one (click to open):
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Last updated 13 Oct 2026