PostgresDB 08006: Connection failure

What is PostgresDB 08006: Connection failure

Check the PostgreSQL service status: On Unix/Linux: sudo service postgresql status or systemctl status postgresqlOn Windows, open Services from the Control Panel and look for PostgreSQL service.Review PostgreSQL Server Logs:Default location varies, but check /var/log/postgresql/ on Linux or the data directory on Windows.Look for entries around the time the error occurred to find specific reasons for failure.Verify Network Connectivity:Ping the database server from the client machine: ping <database_server_ip>If the database is on a remote server, use telnet <database_server_ip> 5432 to check if the PostgreSQL port is reachable.Check Database Connection Configuration:Verify the connection details in your application configuration file or command line, including host, port, user, and password.For a command line test: psql -h <host> -p <port> -U <user> -d <database_name>Ensure PostgreSQL is Listening on the Correct Port and Interfaces:On the database server, check postgresql.conf for listen_addresses and port settings.You can find postgresql.conf typically in the data directory /var/lib/postgresql/<version>/data/ on Linux.Review pg_hba.conf File:Ensure your client’s IP address or subnet is allowed to connect to the database in the pg_hba.conf file, located in the same directory as postgresql.conf.Changes to pg_hba.conf require reloading PostgreSQL: SELECT pg_reload_conf(); or systemctl reload postgresql on the server.Check for Active Connections and Locks:If you can connect through another session or tool, check for excessive connections or locks that might prevent new connections:For active connections: SELECT * FROM pg_stat_activity;For locks: SELECT * FROM pg_locks JOIN pg_class ON pg_locks.relation = pg_class.oid;Restart PostgreSQL Service:If it's safe to do so, try restarting the PostgreSQL service:On Unix/Linux: sudo service postgresql restart or systemctl restart postgresqlOn Windows, use the Services panel to restart the PostgreSQL service.Check System Resources:Ensure the server has sufficient CPU, memory, and disk space:On Unix/Linux, use commands like top, free -m, and df -h.On Windows, use Task Manager or Resource Monitor.