About MAAS events

MAAS events are key to most debugging efforts. Events are state changes that happen to MAAS elements, such as controllers, networks, or machines. These state changes can be caused by MAAS itself, some external agent (such as an external DHCP server), or by users (such as when commissioning a machine). Being able to review events is often essential to debugging or verifying your MAAS system.

Events can be seen in the MAAS logs, in the UI event log, and in output from the CLI events query command. These three sources provide analogous (but somewhat different information). For example, consider the following log listing, obtained by doing a grep "fun-zebra" *.log | grep "transition from" in the MAAS log directory:

maas.log:2022-09-29T15:04:07.795515-05:00 neuromancer maas.node: [info] fun-zebra: Status transition from COMMISSIONING to TESTING
maas.log:2022-09-29T15:04:17.288763-05:00 neuromancer maas.node: [info] fun-zebra: Status transition from TESTING to READY

This information appears this way when events are queried from the CLI:

        {
            "username": "unknown",
            "node": "bk7mg8",
            "hostname": "fun-zebra",
            "id": 170,
            "level": "INFO",
            "created": "Thu, 29 Sep. 2022 20:04:17",
            "type": "Ready",
            "description": "
        },
        {
            "username": "unknown",
            "node": "bk7mg8",
            "hostname": "fun-zebra",
            "id": 167,
            "level": "INFO",
            "created": "Thu, 29 Sep. 2022 20:04:07",
            "type": "Running test",
            "description": "smartctl-validate on sda"
        },

And it appears like this in the UI events log:

You can see that all three outputs are sources of truth, but the messages are somewhat different, include different information, and contain different levels of detail.