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BLACK BOX // prod-web-03Intermediate~12 min

The Silent Web Server

Investigate safely. Narrow the uncertainty. Don't reboot on a hunch.

Scenario

A production Linux web server is responding slowly and sometimes timing out. nginx is technically running, but users are complaining. CPU isn't high. Disk usage 'looks normal' at first glance. SSH works. Your job: investigate safely, narrow the uncertainty, identify the root cause, and choose the safest fix — without touching production blindly.

Click a command above to investigate. Gather evidence before you diagnose.
0 commands run
Monitoring
CPU9% busy / 84% IO wait
Load avg26.4
Memory6.1 / 15 GiB
Disk /100% used
nginxactive (running)
Requeststimeouts ↑
Service status
nginx active (running)
workers up; upstream timeouts rising
app (gunicorn) active (running)
logging verbosely to /var/log/app/debug.log
Recent changes
  • • 03:10 — log-cleanup cron ran: `rm -f /var/log/app/*.log`
  • • no deploys in the last 7 days
  • • no kernel/package updates today