etcd
Distributed key-value store built on Raft, used as the cluster state store for Kubernetes. Covers install, single-node and three-node cluster setup, TLS, RBAC, backup/restore, tuning, and monitoring.
Databases
MariaDB
Setup, security hardening, performance tuning, SSL/TLS, Galera clustering, backup, replication, and monitoring for MariaDB. Includes config snippets, SQL, and troubleshooting tables.
MongoDB
Reference for running MongoDB: installation, configuration, authentication, CRUD, indexing, aggregation, replica sets, sharding, backup, performance tuning, monitoring, and troubleshooting.
PostgreSQL
Setup and operation of a Patroni-managed PostgreSQL 17 cluster with etcd consensus and PgBouncer connection pooling, covering SSL, performance tuning, WAL archiving, PITR, and logical replication.
SQLite
Reference for SQLite as a serverless, single-file relational database: installation, schema and data management, transactions, WAL mode, locking, pragmas, indexing, backups, and performance tuning.