pg_basebackup

pg_basebackup is a utility that is used to create a backup of a PostgreSQL database cluster. This utility creates a copy of the entire database cluster, including all the data files, configuration files, and WAL (Write-Ahead Log) files.

To use pg_basebackup, you'll need to connect to the PostgreSQL server. Once you're connected to the server, you can use pg_basebackup to create a backup of the database cluster. The following command creates a backup in the directory /path/to/backup:

pg_basebackup -h [host] -p [port] -U [username] -D /path/to/backup

This will create a copy of the entire database cluster in the directory /path/to/backup. Note that you may need to specify additional options depending on your specific needs.

Now, let's talk about WAL logs. WAL stands for Write-Ahead Log, which is a mechanism used by PostgreSQL to ensure data consistency and durability. WAL logs are files that contain a record of all changes made to the database.

When you create a backup using pg_basebackup, the backup will include all the WAL logs up to the point at which the backup was created. This ensures that you can recover your database to a consistent state in the event of a failure.