Tag: linux

SSHFS mounts remote filesystems over SSH so you can browse and edit files locally, faster than scp for interactive work.

Decode systemctl status: Active state, CGroup processes, recent logs, loaded/enabled state. What each field tells you.

Understand SSH agent forwarding security risks. When it's safe (almost never), and better alternatives like ProxyJump for jump hosts.

Check SSD health, find excessive write patterns, use noatime, move logs to tmpfs to extend lifespan.

Essential journalctl commands: -u, -f, --since, -p, -k, -b, --no-pager, JSON output. The queries you need on a broken server at 2 AM.

Fix SSH timeouts: ServerAliveInterval, ServerAliveCountMax, ClientAliveInterval. Understand NAT, firewalls, and TCP keepalive.

ss replaces netstat on modern Linux: faster, shows more socket detail, and reads from the kernel. Every netstat command you rely on, rewritten for ss.

PATH is different in cron, stdout is muted, and MAILTO breaks silently. Learn cron traps and how to debug them.

Master SSH ControlMaster, ControlPath, and ControlPersist. Reuse connections for lightning-fast SSH, SCP, and rsync operations.

Why Linux kills your app with no warning. Understand the OOM killer, read dmesg logs, and shield critical processes with oom_score_adj and swap.

Practical find command examples: -mtime, -newer, -type, -exec vs xargs, -not, size filters. The patterns you google every time.

Master ~/.ssh/config: Host aliases, HostName, User, Port, IdentityFile, ProxyJump. Stop typing long SSH commands. One-line setup.