SRE Guide: How to Keep Databases Reliable With Backups, Pooling, and Monitoring

A site reliability engineering (SRE) post on DEV Community outlines practical techniques for maintaining database reliability in production environments. A key lesson shared is that untested backups are unreliable — the author discovered their backups had been silently failing for three weeks after an S3 bucket policy change, only realizing it during a data corruption incident. To prevent recurrence, the team built an automated weekly restore-test script that validates backup integrity against live production data, catching four backup issues over the past year. The article also covers reducing PostgreSQL connection overhead using PgBouncer in transaction mode, which can cut backend connections from hundreds down to around 25. Additional recommendations include monitoring replication lag, identifying slow queries via pg_stat_statements, performing zero-downtime schema migrations with concurrent indexing, and tracking key dashboard metrics such as cache hit ratio, query latency percentiles, and disk growth rate.