The JusDB Database Engineering Blog

RTO and RPO drive backup decisions. This guide covers mysqldump, XtraBackup, pgBackRest, WAL archiving, S3 object lock, and the 3-2-1-1-0 backup rule.

Monitor MySQL and PostgreSQL with Prometheus, Grafana, and PMM. Covers mysqld_exporter, postgres_exporter, alert rules, and production dashboard configuration.

Secure your MySQL and PostgreSQL databases — TLS, at-rest encryption, role-based access, and audit logging

Running a single PMM server is a single point of failure for your database monitoring. Here's how to set up PMM in an HA configuration with failover and shared storage.

Essential MySQL diagnostic queries every DBA needs. Quickly identify slow queries, lock contention, replication lag, memory issues, and connection problems.

A comprehensive guide to MySQL replication lag — why it happens, why Seconds_Behind_Master lies, how to measure accurately with pt-heartbeat, and how to fix it with multi-threaded replication and LOGICAL_CLOCK parallelism.

Deploy PMM to get deep MySQL and PostgreSQL visibility — query analytics, dashboards, and alerting in one tool

A production guide to MySQL slow query log — enabling with long_query_time and log_queries_not_using_indexes, analyzing with pt-query-digest, reading EXPLAIN output, and fixing full table scans and N+1 loops.

Most MySQL maintenance tasks still rely on cron, but systemd timers offer better logging, dependency management, and failure handling. Here's how to convert your MySQL maintenance scripts to systemd services.

Running MongoDB without TLS exposes your data to network interception and man-in-the-middle attacks. Here's how to configure TLS/SSL across your MongoDB replica set.

MySQL 8.0 exposes error logs through performance_schema.error_log — enabling SQL-based filtering by severity, component, and timestamp without grep-ing log files.

MySQL InnoDB tablespace encryption (TDE) encrypts data pages on disk without changing application code — using a two-tier keyring architecture that separates the master key from table keys.