Alert catalogue

Software 3.4 · codes are stable across the 3.x line · reviewed 2026-08-19

How alerting behaves

An alert opens once and stays open until its cause is gone. It is not re-sent every poll, it is not re-sent after an acknowledgement, and closing is automatic — a jam that someone clears is closed by the next successful poll, without anyone telling the unit.

Deduplication	One open alert per code per device
Flap protection	An alert that opens and closes three times in an hour is held open for four hours
Delivery	Mail to the recipients on the rule; everything is visible in the console regardless
Digest	Informational alerts are batched into one mail per day at 07:30
Escalation	A critical alert open for more than 4 hours is re-sent once, to the escalation address

1xx — device

Code	Severity	Means	Action
MLU-101	info	New device discovered	Label it and check the profile match.
MLU-102	info	Device address changed	None. Expect it after a DHCP lease change.
MLU-103	warning	Device answered but with a different serial	A replacement at the same address. Confirm, then let the new record stand.
MLU-104	warning	Unreachable for three consecutive passes	Powered off, moved, or SNMP blocked. Check the device before the network.
MLU-105	critical	Device reports a fault stopping printing	Jam, cover, or engine error. The alert text carries the device’s own message.
MLU-106	warning	Counter reset detected	See resets. Do not export until reviewed.
MLU-107	warning	Implausible counter jump	Verify against the device’s configuration page.
MLU-108	info	Device firmware version changed	None. Useful when a fault starts the same week.
MLU-109	warning	Two devices reporting the same serial	See identity. Neither is billed until resolved.

2xx — supplies

Code	Severity	Means	Action
MLU-201	info	Supply below warning threshold	Goes on the weekly ordering list.
MLU-202	warning	Supply below critical threshold	Carry a replacement on the next visit.
MLU-203	critical	Supply empty, device stopped	Replace now.
MLU-204	warning	Waste container near full	Order the container; the device will stop outright when it fills.
MLU-205	info	Supply replaced	None. This is how a cartridge swap is recorded.
MLU-206	info	Supply stopped reporting a level	Usually a third-party cartridge. Excluded from ordering until it reports again.
MLU-207	warning	Supply consumption far above the device’s own average	Check for a leaking cartridge or a job printing solid fills.

3xx — appliance

Code	Severity	Means	Action
MLU-301	info	Unit restarted	None if it was planned. Two in a day is not planned.
MLU-302	warning	Clock offset above 30 s	NTP unreachable or blocked. Fix before month end.
MLU-303	warning	Storage above 80 %	Almost always held jobs. See retention.
MLU-304	critical	Storage above 95 %	The queue stops accepting jobs. Purge or raise the limits.
MLU-305	warning	Backup has not run for 14 days	Check the destination share, not the unit.
MLU-306	warning	Mail delivery failing	Relay, credentials or a changed policy. Alerts are still in the console.
MLU-307	critical	Collection service restarted repeatedly	Take a diagnostic bundle before rebooting.
MLU-308	info	Software updated	None. Records the version change.
MLU-309	warning	Ambient temperature above 45 °C	Ventilate the cabinet. The unit throttles collection above 50 °C.

4xx — queue

Code	Severity	Means	Action
MLU-401	warning	Queue full, oldest jobs dropped	Raise the limit or shorten the hold time.
MLU-402	warning	Release failed — target device refused the job	Check 9100 outbound and that the device is not in an error state.
MLU-403	info	Jobs expired unreleased	None. A steady stream of these means the hold time is too short for the floor.
MLU-404	warning	One user above the job limit	Usually a looping workstation. Cancel and tell them.
MLU-405	critical	Queue service not accepting connections	Nothing prints. Restart the service, then take a bundle.
MLU-406	warning	Card or PIN rejected five times for one account	Card not bound, or a shared account. Rebind on the release page.

Quiet hours and suppression

Quiet hours hold non-critical mail until the morning. Critical alerts always go out — a queue that stopped at 04:00 matters at 04:00, because the floor arrives at 08:00.

mluctl alert quiet set --from 19:00 --to 07:00 --except critical
mluctl alert rule add --code MLU-201 --mail supplies@printdoc.digital --digest
mluctl alert suppress MLU-206 --device 10.20.4.44 --until 2026-12-31 --reason "third-party toner, known"
mluctl alert list --open

Suppress with an end date, always. An indefinite suppression is how a site ends up not knowing about a device for two years. The unit requires --until and refuses anything further away than eighteen months.