mrgreen007/pgpool repository overview

⁠Pgpool (Bitnami-based Docker Image)

⁠Overview

This Docker image packages Pgpool-II using the official Bitnami pgpool container source code. It behaves identically to the official Bitnami pgpool image, including:

• Directory structure
• Environment variables
• Startup scripts
• Configuration files
• Runtime behavior

The image supports multi-architecture builds (amd64 and arm64).

⁠What is Pgpool-II?

Pgpool-II is a middleware layer for PostgreSQL that sits between PostgreSQL clients and backend PostgreSQL servers.

It provides:

• Connection pooling
• Load balancing for read queries
• High availability and failover support
• Replication management
• Online recovery

Pgpool-II is commonly used in setups with:

• Primary and replica PostgreSQL
• High-availability clusters
• Read scaling requirements

⁠Configuration

Configuration is handled exactly the same way as the Bitnami pgpool image.

⁠Primary configuration files

• pgpool.conf
• pool_hba.conf
• pcp.conf

These files are located in:

/opt/bitnami/pgpool/conf

You typically override them using:

• Environment variables
• Mounted volumes
• Custom configuration files

⁠Environment Variables

The image supports all standard Bitnami pgpool environment variables, including (but not limited to):

• PGPOOL_BACKEND_NODES
• PGPOOL_SR_CHECK_USER
• PGPOOL_SR_CHECK_PASSWORD
• PGPOOL_POSTGRES_USERNAME
• PGPOOL_POSTGRES_PASSWORD
• PGPOOL_ENABLE_LOAD_BALANCING

Refer to Bitnami pgpool documentation for the complete list and behavior.

⁠Ports

The container exposes:

5432

This is the Pgpool listening port for PostgreSQL clients.

⁠Running the Image

Basic example:

docker run -d \
  --name pgpool \
  -p 5432:5432 \
  mrgreen007/pgpool:4.6.4

Example with environment variables:

docker run -d \
  --name pgpool \
  -p 5432:5432 \
  -e PGPOOL_BACKEND_NODES="0:postgres-primary:5432,1:postgres-replica:5432" \
  -e PGPOOL_POSTGRES_USERNAME=postgres \
  -e PGPOOL_POSTGRES_PASSWORD=secret \
  mrgreen007/pgpool:4.6.4

⁠Notes on Bitnami Source Usage

This image is built from Bitnami pgpool container source code, preserving:

• Bitnami startup logic
• File layout
• Configuration behavior

No functional changes are introduced.