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Pairing a node

1. Get a code​

Open the nomctl alerts bot in Telegram and send /start. It replies with an 8-character pairing code, valid for 10 minutes and usable once. You can hold up to five unused codes.

2. Pair​

On the node:

sudo nomctl alerts setup

It asks for the code and a name for the node (default: the hostname), pairs with the relay, writes /etc/nomctl/alerts.json, installs and starts nomctl-alerts.service, and sends a test message. Your chat receives "paired and reporting" and then the test.

Flags skip the prompts, which is how to script it:

sudo nomctl alerts setup --code AB3K7QWX --name pillar-1

Released binaries default to the community relay at https://alerts.zenon.info. --relay or NOMCTL_RELAY_URL point at another one.

The name is also the pillar name​

If a registered pillar has the same name as the node, setup says "monitoring pillar NAME (rank N)", stores it, and the pillar_missed alert becomes active. nomctl status and top then show the pillar's rank and produced versus expected momentums for the epoch.

If the names differ, set it afterwards; the value is checked against the pillar list:

sudo nomctl alerts set pillar.name MyPillar
sudo nomctl alerts set pillar.name ""      # clear

More than one node​

Pair as many nodes as you like to the same chat. Names must be unique per chat, and every message starts with the node's name.

Managing on the node​

sudo nomctl alerts status                 # pairing, service, current state of each alert
sudo nomctl alerts list                   # alerts and thresholds
sudo nomctl alerts set disk_low.min_free_gb 30
sudo nomctl alerts disable backup_stale
sudo nomctl alerts enable backup_stale
sudo nomctl alerts test
sudo nomctl alerts unpair                 # keeps credentials if the relay is unreachable; --force removes them anyway

Threshold and switch changes reach the running daemon immediately. Duration thresholds are limited to 30 minutes, the amount of history the daemon keeps.

If something fails during setup​

If pairing succeeds but the service cannot be installed, setup undoes the pairing at the relay so you do not get a node silent alert for a node that never reported. If even that fails, the credentials are kept and setup tells you to run nomctl alerts unpair.