Duplicate FQDN can be configured on MAAS via CLI or API

[Takenori MATSUMOTO]

It makes sense to be able to:

1. Raise error response in case of user specify duplicated hostname via MAAS GUI or API.

But this can't be done, because MAAS can configure duplicated hostname.

[Julian Edwards (julian-edwards)]

Hi Takenori,

The database has a unique key on hostname, can you tell me exactly what you're
doing to achieve the duplicate please?

[Takenori MATSUMOTO (takenori-matsumoto)]

Hi Julian,

From MAAS GUI, you're right. I could not configure duplicated hostname from GUI.
The following is procedure.

Step-1
$ maas-cli maas nodes list
See [1] below. There are two entry "juju.master" and "ecndt.master"

Step-2
$ maas-cli maas node update node-cbcd5156-caaa-11e3-ac04-525400b9c4a2 hostname="juju.master"
I try to update hostname from "ecndt.master" to "juju.master", where "juju.master" is already there.

Step-3
$ maas-cli maas nodes list
See [2] below. As you can see, now there are two "juju.master".

[1]
[
    {
        "status": 4,
        "macaddress_set": [
            {
                "resource_uri": "/MAAS/api/1.0/nodes/node-2a19b962-8da1-11e3-923f-525400b9c4a2/macs/52:54:00:e9:66:d7/",
                "mac_address": "52:54:00:e9:66:d7"
            }
        ],
        "netboot": true,
        "hostname": "juju.master",
        "power_type": "virsh",
        "system_id": "node-2a19b962-8da1-11e3-923f-525400b9c4a2",
        "architecture": "i386/generic",
        "tag_names": [
            "juju",
            "virtual"
        ],
        "resource_uri": "/MAAS/api/1.0/nodes/node-2a19b962-8da1-11e3-923f-525400b9c4a2/"
    },
    {
        "status": 0,
        "macaddress_set": [
            {
                "resource_uri": "/MAAS/api/1.0/nodes/node-cbcd5156-caaa-11e3-ac04-525400b9c4a2/macs/52:54:00:f0:7e:24/",
                "mac_address": "52:54:00:f0:7e:24"
            }
        ],
        "netboot": true,
        "hostname": "ecndt.master",
        "power_type": "",
        "system_id": "node-cbcd5156-caaa-11e3-ac04-525400b9c4a2",
        "architecture": "i386/generic",
        "tag_names": [],
        "resource_uri": "/MAAS/api/1.0/nodes/node-cbcd5156-caaa-11e3-ac04-525400b9c4a2/"
    }
]

[2]
[
    {
        "status": 4,
        "macaddress_set": [
            {
                "resource_uri": "/MAAS/api/1.0/nodes/node-2a19b962-8da1-11e3-923f-525400b9c4a2/macs/52:54:00:e9:66:d7/",
                "mac_address": "52:54:00:e9:66:d7"
            }
        ],
        "netboot": true,
        "hostname": "juju.master",
        "power_type": "virsh",
        "system_id": "node-2a19b962-8da1-11e3-923f-525400b9c4a2",
        "architecture": "i386/generic",
        "tag_names": [
            "juju",
            "virtual"
        ],
        "resource_uri": "/MAAS/api/1.0/nodes/node-2a19b962-8da1-11e3-923f-525400b9c4a2/"
    },
    {
        "status": 0,
        "macaddress_set": [
            {
                "resource_uri": "/MAAS/api/1.0/nodes/node-cbcd5156-caaa-11e3-ac04-525400b9c4a2/macs/52:54:00:f0:7e:24/",
                "mac_address": "52:54:00:f0:7e:24"
            }
        ],
        "netboot": true,
        "hostname": "juju.master",
        "power_type": "",
        "system_id": "node-cbcd5156-caaa-11e3-ac04-525400b9c4a2",
        "architecture": "i386/generic",
        "tag_names": [],
        "resource_uri": "/MAAS/api/1.0/nodes/node-cbcd5156-caaa-11e3-ac04-525400b9c4a2/"
    }
]

[Jason Hobbs (jason-hobbs)]

Hi Takenori, what version of MAAS is this?

[Takenori MATSUMOTO (takenori-matsumoto)]

Hi Jason, I verify it on 14.04LTS and MAAS version is 1.5

[Jason Hobbs (jason-hobbs)]

The issue is that when DNS is managed, MAAS replaces the domain name portion of a hostname with the domain name of the cluster, if the node has a hostname. So, when DNS management is enabled, nodes with hostnames "a", "a.b" and "a.c" all have the same FQDN. There is no uniqueness check for FQDN, only hostname.

There's another way to get into this state:

1) Start with DNS management disabled for the cluster.
2) Create two nodes: "a.b" and "a.c".
3) Enable DNS management for the cluster, with domain name "d".
4) Now you have two nodes with FQDN "a.d".

[Jason Hobbs (jason-hobbs)]

Another way to get into this state:

1) Create two clusters, cluster_a and cluster_b. cluster_a has DNS management enabled with domain 'a'. cluster_b has DNS management disabled
2) On cluster_a, create a node with hostname "x". Its fqdn is now "x.a"
3) On cluster_b, create a node with hostname "x.a". Its fqdn is now "x.a"