Tag: linux

Idle SSH sessions and long-lived connections die because the OS gives up first. What the three keepalive sysctls mean, how to tune them, and per-socket options.

Set up auditd to log every sudo command and file change on Linux: auditctl rules, ausearch, aureport, and shipping logs to Loki or Elasticsearch for compliance.

Your VM's clock is off by minutes, NTP says it's synced, yet the system keeps drifting. Here's why the hypervisor is the real culprit, and how to fix it.

MTU mismatches silently break large file transfers, backups, and video calls. Here's how to find and fix the wrong frame size on your network.

Cisco's OpenH264 download server geoblocks sanctioned regions, breaking Firefox and Flatpak installs. Four practical fixes, ranked simple to nuclear.

Set up a WireGuard VPN kill switch and prevent DNS leaks on Linux. Practical iptables rules, resolv.conf locking, and systemd-resolved config.

Run BGP in your home lab with FRRouting. Covers iBGP vs eBGP, FRR installation, basic BGP config, peering with OPNsense, route filtering, and when BGP is actually worth the complexity.

Suricata beats Snort on multi-threading and EVE JSON logging. Side-by-side IDS/IPS breakdown with Suricata install, suricata.yaml config, and OPNsense setup for home labs.

DNS broke again. The command sequence that finds it: verify the resolver, reach a server, dig the record, trace the query path, check reverse lookups.

Podman skips the root daemon Docker needs. Quadlets let systemd manage containers natively, with auto-updates and health checks, for self-hosting without Compose.

Learn Linux capabilities to drop root privileges without breaking your apps. Master cap_drop, cap_add in Docker, and setcap for fine-grained privilege control.

Master the curl flags that'll save you hours debugging APIs, downloads, and web requests. From -X to --compressed, here's what actually matters.