I like Nginx load balancing because it stays boring when the traffic pattern is boring, and that is a compliment. When a setup is healthy, most of the work is invisible. The trouble starts when the upstream layer is copied from an old blog post, nobody logs which backend answered the request, and an intermittent
Nginx Upstream Load Balancing Configuration: What I Actually Tune in Production Read Post »
A denial-of-service vulnerability in OpenSSL, named HollowByte by Okta’s Red Team, enables a remote unauthenticated attacker to permanently exhaust server memory using a crafted 11-byte TLS handshake payload. The flaw was quietly fixed in a multi-branch OpenSSL release on June 9, 2026. No official CVE advisory was published by the OpenSSL project at the time
OpenSSL HollowByte: 11-Byte TLS Payload Causes Server Memory Exhaustion Read Post »
When a site feels slow or unreliable, I still start with logs more often than dashboards. Metrics help, but logs tell me what actually happened to specific requests. They also expose the ugly details dashboards smooth over: repeated client aborts, a sudden flood of 404s from one broken deploy, one upstream timing out while another
Nginx Log Analysis: How I Read Access and Error Logs Without Drowning in Noise Read Post »
User management is basic Linux administration in the same way plumbing is basic house maintenance: you can ignore it right up until the day it leaks into everything else. Bad user and group hygiene creates permission problems, weak sudo rules, confusing service ownership, and messy offboarding. Good hygiene is not glamorous, but it prevents a
Linux User and Group Management: A Practical Guide for Sysadmins Read Post »
sysctl is one of those Linux tools that attracts two kinds of bad advice. One camp never touches it and leaves obvious workload mismatches unaddressed. The other pastes giant “performance tuning” blocks from random forum posts into /etc/sysctl.conf, reboots, and hopes for free speed. I do not recommend either approach. Kernel parameters absolutely matter, but
Linux sysctl Performance Tuning Parameters Read Post »
When a service “is down,” the network is usually blamed first and understood last. I have seen people restart perfectly healthy daemons because they never checked whether the port was listening, whether a firewall was dropping the traffic, or whether the client was even talking to the right IP. Good network troubleshooting is less about
Linux Network Troubleshooting with ss, netstat, tcpdump, and Friends Read Post »
Memory problems on Linux rarely start with the machine being literally out of RAM. They usually start with someone looking at free -h, seeing almost all memory marked as used, and assuming the kernel is leaking, the database is bloated, or swap is somehow the root of every evil. I have seen good servers rebooted
Linux Memory Management and Swap Configuration Read Post »
Disk I/O problems are some of the easiest Linux performance issues to misread. CPU looks fine, memory is not completely exhausted, load average is high, and the server still feels sticky. Commands hang for a second or two. Databases stutter. Backups start slowly and then drag everything else with them. That is usually when I
Linux Disk I/O Monitoring with iostat, iotop, and Real Bottleneck Hunting Read Post »
Rate limiting is one of those things that’s easy to get wrong in both directions — too loose and it does nothing, too tight and you start blocking real users. I’ve tuned rate limiting configs on production sites a few times and I’ve made both mistakes. Here’s what I’ve learned about how Nginx rate limiting
Nginx Rate Limiting: How to Stop Abuse Without Breaking Legitimate Traffic Read Post »
Sometimes you need to protect a URL quickly — a staging environment, an admin panel, a Prometheus metrics endpoint, internal documentation. Setting up a full authentication system is overkill. Nginx’s built-in basic authentication handles these cases well. Basic auth has a reputation for being insecure, but that reputation is mostly from HTTP days. Over HTTPS,
Nginx Basic Auth: Quick Access Control Without a Full Auth System Read Post »