Learning Ceph - Second Edition

CRUSH dump

This command presents much the same information as ceph osd tree, though in a different, JSON, format. Note a peek into the additional bucket types that Ceph predefines for large and complex deployments. As before many of the 2899 lines of output this command yielded on the author's reference cluster are cropped for brevity.

    # ceph osd crush dump | more
    {
        "devices": [
            {
                "id": 0,
                "name": "osd.0"
            },
            {
                "id": 1,
                "name": "osd.1"
            },
             ...
            {
                "id": 286,
                "name": "osd.286"
            }
        ],
        "types": [
            {
                "type_id": 0,
                "name": "osd"
            },
            {
                "type_id": 1,
                "name": "host"
            },
            {
                "type_id": 2,
                "name": "chassis"
            },
            {
                "type_id": 3,
                "name": "rack"
            },
            {
                "type_id": 4,
                "name": "row"
            },
            {
                "type_id": 5,
                "name": "pdu"
            },
            {
     "type_id": ...