Error: PostgreSQL Connection Refused Troubleshooting

When using MCP postgres tool and encountering Connection refused error.

Causes

1. PostgreSQL service not running
2. Wrong port configuration
3. Wrong listen address
4. Firewall blocking

Troubleshooting Steps

Step 1: Check PostgreSQL Service

brew services list | grep postgresql
brew services start postgresql

Step 2: Check Port Listening

lsof -i :5432

Step 3: Check PostgreSQL Config

grep listen_addresses /path/to/postgresql.conf

Step 4: Check Firewall

sudo ufw allow 5432/tcp

Step 5: Test Connection

psql -h localhost -p 5432 -U username -d dbname

Next Steps

• Authentication Failed Error
• PostgreSQL Configuration