PostgreSQL server is not running or unreachable on the configured port. Network firewall or security group blocks the connection. Connection pool exhausted — too many concurrent connections. Server crashed or was restarted mid-session

Step 1: Verify the PostgreSQL server is running: `pg_isready -h -p `.. Step 2: Check firewall rules and security groups to ensure port 5432 (or custom port) is open.. Step 3: Review `pg_hba.conf` to confirm the client IP is allowed.. Step 4: Check `max_connections` in `postgresql.conf` and compare with active connections via `SELECT count(*) FROM pg_stat_activity`.. Step 5: Review PostgreSQL server logs (`/var/log/postgresql/`) for crash or OOM events.

High severityconnectivity

Power BI Refresh Error:
08000

What does this error mean?

A generic connection-level error occurred. The client could not establish or maintain a session with the PostgreSQL server.

Common causes

1PostgreSQL server is not running or unreachable on the configured port
2Network firewall or security group blocks the connection
3Connection pool exhausted — too many concurrent connections
4Server crashed or was restarted mid-session

How to fix it

1Step 1: Verify the PostgreSQL server is running: `pg_isready -h <host> -p <port>`.
2Step 2: Check firewall rules and security groups to ensure port 5432 (or custom port) is open.
3Step 3: Review `pg_hba.conf` to confirm the client IP is allowed.
4Step 4: Check `max_connections` in `postgresql.conf` and compare with active connections via `SELECT count(*) FROM pg_stat_activity`.
5Step 5: Review PostgreSQL server logs (`/var/log/postgresql/`) for crash or OOM events.

Frequently asked questions

How do I prevent 08000 errors in automated pipelines?

Add retry logic with exponential backoff, validate data quality before loading, and monitor pipeline failures in MetricSign to catch this error early.

Official documentation: https://www.postgresql.org/docs/current/errcodes-appendix.html