Preventive Maintenance, Network Edition

The checks that never make headlines: batteries, firmware lags, spare spares, and the drag they put on outages.

Emergency maintenance is a scheduling failure wearing a costume. The unglamorous calendar is what keeps the phone quiet, and it fits on one page.

The rhythm

• Monthly: config backups verified by restore, not by filesize; certificate expiry sweep; capacity graphs eyeballed with last quarter overlaid
• Quarterly: firmware on the laggers, failover exercised for real, the spare-parts shelf counted — RMA the dead spare before you need it
• Annually: docs rewrite, runbook rehearsal with the people who did not write it, the contact tree called top to bottom

What drift looks like

The UPS that beeps only in the dark. The console cable on a box three sites over. The monitoring that turned green because someone silenced the check during a remodel.

None of it heroic. The point of the rhythm is smaller, funereal: incidents become five-minute events with a known shape, not archaeological digs.