---
title: "Reliability and the Write-Ahead Log"
id: wal
pg_version: "20devel"
---

<a id="wal"></a>

# Reliability and the Write-Ahead Log

## Table of Contents

- [28.1. Reliability](wal-reliability.md)
- [28.2. Data Checksums](checksums.md)
  - [28.2.1. Offline Enabling of Checksums](checksums.md#checksums-offline-enable-disable)
  - [28.2.2. Online Enabling of Checksums](checksums.md#checksums-online-enable-disable)
- [28.3. Write-Ahead Logging (WAL)](wal-intro.md)
- [28.4. Asynchronous Commit](wal-async-commit.md)
- [28.5. WAL Configuration](wal-configuration.md)
- [28.6. WAL Internals](wal-internals.md)

This chapter explains how to control the reliability of PostgreSQL, including details about the Write-Ahead Log.