Showing 8 posts tagged with "linux"
Ubuntu Linux Time Synchronization: systemd-timesyncd, Chrony, NTP & Clock Drift Mitigation
Ubuntu Linux system time synchronization guide: systemd-timesyncd, chrony NTP configuration, hwclock RTC sync, and clock drift mitigation.
Automated Rotating Backups: Bash Disaster Recovery, Cron & Atomic Snapshots
Architectural guide to automated rotating backups: Bash disaster recovery scripts, non-blocking MySQL dumps, GFS rotation schemes, and cron hardening.
Automated Free SSL/TLS Certificates with Certbot, Let's Encrypt & Nginx: Zero-Downtime Linux Guide
Architectural guide to installing and configuring free automated SSL/TLS certificates with Let's Encrypt, Snap-based Certbot, and hardened Nginx reverse proxy.
Dead Man's Switch Architecture: Heartbeats, Leader Leases & Distributed Failovers
Architectural deep dive into the Dead Man's Switch pattern: distributed consensus heartbeats in Raft, Linux /dev/watchdog timers, canary deployment rollbacks, and cryptographic fail-safe design.
Mitigating Constant Brute Force Attacks: DirectAdmin BFM, Fail2ban, CSF & IPTables Rate Limiting
Comprehensive Linux server security runbook: automating IP bans with DirectAdmin Brute Force Monitor, CSF/LFD, Fail2ban, and kernel-level iptables rate limiting to eliminate alert fatigue.
Linux Mail Server Troubleshooting: Exim Queue Diagnostics & Modern MTA
Comprehensive sysadmin guide to Linux Exim mail queue troubleshooting: diagnosing frozen queues, exim.conf syntax checks, and cloud SMTP relay migration.
Exim MTA Architecture: System Filter Debugging, Runbooks & Queue Management
In-depth diagnostic runbook for Exim Mail Transfer Agent (MTA) outages: resolving system filter syntax errors, testing with exim -bf, unfreezing queues, and DirectAdmin mail administration.
Cloud Economics vs. Bare-Metal Infrastructure: Lessons from 15 Years of DevOps & Private Clusters
Comprehensive architectural and financial analysis of public cloud versus bare-metal infrastructure: AWS EC2 egress taxes, noisy neighbor virtualization jitter, 3-year TCO modeling, and Linux sysctl tuning.