Database

How to Configure Database Connection Pooling with PgBouncer on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure Database Connection Pooling with PgBouncer on RHEL 9

PgBouncer is a lightweight PostgreSQL connection pooler that solves one of PostgreSQL’s most common scalability problems: the high cost of creating new database connections. Unlike MySQL, PostgreSQL spawns a new OS process for each client connection, which consumes approximately 5–10 MB of memory and requires significant CPU time to establish. Web applications that open hundreds […]

Read more
How to Manage Systemd Services and Units on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Manage Systemd Services and Units on RHEL 9

Systemd is the init system and service manager for RHEL 9 — it is PID 1, the parent of every other process on the system. Understanding how to manage systemd services is foundational to every other administrative task: installing Nginx means enabling the nginx service; configuring a database means understanding its unit file; debugging a […]

Read more
How to Configure Zabbix Agent on Debian 12 — step-by-step Debian 12 tutorial on Progressive Robot

How to Configure Zabbix Agent on Debian 12

Introduction This guide explains how to Configure Zabbix Agent on Debian 12 on Debian 12 Bookworm. Debian Bookworm uses systemd for service management, nftables as the underlying packet filter (with ufw or iptables front-ends still available), and AppArmor for mandatory access control. Every command is designed for a minimal Debian 12 install with the standard […]

Read more
How to Install MySQL 8 on Debian 12 — step-by-step Debian 12 tutorial on Progressive Robot

How to Install MySQL 8 on Debian 12

Introduction Deploying install mysql 8 on debian 12 on a Debian 12 Bookworm machine is straightforward thanks to Debian’s policy-compliant packaging. Unlike rpm-based distributions, Debian stores configuration helpers in /etc/default/, uses update-rc.d for older init scripts, and provides dpkg-reconfigure for interactive package configuration. This tutorial stays on the systemd path throughout. Prerequisites Ensure Debian 12 […]

Read more
How to Configure Redis Cluster and Sentinel on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure Redis Cluster and Sentinel on RHEL 9

A single Redis instance has two failure modes: if the server goes down, all cached data is lost and every request hits the origin database; and if the dataset grows beyond a single server’s RAM, there’s no built-in way to distribute it. Redis provides two solutions: Redis Sentinel for high availability (automatic failover with a […]

Read more
How to Secure MySQL on CentOS Stream 9 — step-by-step CentOS Stream 9 tutorial on Progressive Robot

How to Secure MySQL on CentOS Stream 9

Introduction CentOS Stream 9 ships with a stable, security-hardened base that makes deploying secure mysql on centos stream 9 both straightforward and auditable. This tutorial covers the complete procedure for how to Secure MySQL on CentOS Stream 9, including dnf module streams where applicable, systemd unit management, and the firewalld rules required for network-facing services. […]

Read more
Common Problems 119955

Debian 12 APT Lock Contention During Updates

🟡 Medium   ⏱ 5–30 min  Last verified: 8 January 2024 Affected versions: Debian 12 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & […]

Read more
Common Problems 114560

Incorrect Tuned Profile Causing Performance Issues

🟡 Medium   ⏱ 5–30 min  Last verified: 5 January 2024 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs References & Further […]

Read more
How to Install MongoDB on FreeBSD 14 — step-by-step FreeBSD 14 tutorial on Progressive Robot

How to Install MongoDB on FreeBSD 14

Introduction This guide explains how to Install MongoDB on FreeBSD 14 on FreeBSD 14. FreeBSD uses the pkg(8) binary package manager, rc.conf(5) for service startup configuration, and pf(4) as its primary packet filter. There is no SELinux or AppArmor — instead, FreeBSD provides the MAC (Mandatory Access Control) framework and Capsicum for fine-grained privilege separation. […]

Read more
How to Set Up ProxySQL for MySQL Load Balancing on Debian 12 — step-by-step Debian 12 tutorial on Progressive Robot

How to Set Up ProxySQL for MySQL Load Balancing on Debian 12

Introduction How to Set Up ProxySQL for MySQL Load Balancing on Debian 12 is a fundamental operation for any administrator maintaining a Debian 12 Bookworm server. Debian 12 Bookworm ships with the Linux 6.12 kernel, updated toolchains, and a fully refreshed package archive — meaning version numbers, configuration file paths, and some dependency chains differ […]

Read more
CHAT