dhcp snippet create fail when dhcp subnet is relayed

[Alexander]

We have 2 subnets under MaaS control:
1. 10.70.1.0/24 where rackd is installed
2. 10.80.1.0/24 with dhcp-relay throw 10.70.1.0/24
and I am trying to add dhcp snippet to this subnets.

a) I don't have any problem with 10.70.1.0/24.
ubuntu@maas1:~$ maas admins dhcpsnippets create name=cli_snippet_test value="authoritative;" description="" subnet="10.70.1.0/24"
Success.
Machine-readable output follows:
{
    "name": "cli_snippet_test",
    "description": "",
    "enabled": true,
    "node": null,
    "subnet": {
        "name": "10.70.1.0/24",
        "vlan": {
            "vid": 1101,
            "mtu": 1500,
            "dhcp_on": true,
            "external_dhcp": null,
            "relay_vlan": null,
            "name": "VPC Infrastructure Cloud1",
            "fabric": "XPT_Cloud1",
            "secondary_rack": "8mawdr",
            "space": "INFRA",
            "primary_rack": "7a7ggh",
            "id": 5020,
            "fabric_id": 0,
            "resource_uri": "/MAAS/api/2.0/vlans/5020/"
        },
        "cidr": "10.70.1.0/24",
        "rdns_mode": 2,
        "gateway_ip": "10.70.1.254",
        "dns_servers": [
            "10.70.1.81"
        ],
        "allow_proxy": true,
        "active_discovery": false,
        "managed": true,
        "space": "INFRA",
        "id": 14,
        "resource_uri": "/MAAS/api/2.0/subnets/14/"
    },
    "value": "authoritative;",
    "history": [
        {
            "id": 50,
            "value": "authoritative;",
            "created": "Fri, 28 Dec 2018 00:12:33 -0000"
        }
    ],
    "global_snippet": false,
    "id": 4,
    "resource_uri": "/MAAS/api/2.0/dhcp-snippets/4/"
}

b) but I got an error, when tryed to add snippet to 10.80.1.0/24 configuration and configuration was not changed:
ubuntu@maas1:~$ maas admins dhcpsnippets create name=cli_snippet_test value="authoritative;" description="" subnet="10.80.1.0/24"
Unable to validate DHCP config, no available rack controller connected.

MAAS version: 2.4.2 (7034-g2f5deb8b8-0ubuntu1)

[Adam Collard (adam-collard)]

This bug has not seen any activity in the last 6 months, so it is being automatically closed.

If you are still experiencing this issue, please feel free to re-open.

MAAS Team

[Erlon R. Cruz (sombrafam)]

Patches are ready. Just waiting for launcpad repo to be fixed.

[Andrey Kirilochkin (andreika-mail)]

I have the same behavior on maas 3.2.3. Fix is not working.
The same net config.

[Patrick Hampson (patrickhampson)]

Confirmed as well in maas 3.2.4. Many subnets / fabrics relayed to a single rack controller.

[Erlon R. Cruz (sombrafam)]

Hi folks, how are you confirming if it's working or not? The way I do is by checking the MAAS dhcpd.conf file[1] to see if has the snippet's config. For my case I can see the new snippet section listed every snippet I create.

           #
           # Subnet DHCP snippets
           #
           # Name: s1
           max-lease-time 100;
           pool {
              # No DHCP snippets for pool

              range 192.168.100.191 192.168.100.254;
           }

This is how I create it[2].

We might be creating the network and the snippets in different ways. If possible, can you
post the output of the following commands (properly adapted to your environment):

PROFILE=admin
MAAS=http://10.10.20.2:5240/MAAS/

maas login $PROFILE $MAAS `cat ~/maas-apikey.txt`

maas $PROFILE networks read
maas $PROFILE dhcpsnippets read
maas $PROFILE fabrics read
maas $PROFILE ipranges read
maas $PROFILE rack-controllers read
maas $PROFILE subnets read
for i in `maas $PROFILE fabrics read | jq ".[]|.id"`; do maas $PROFILE vlans read $i; done

[1] /var/snap/maas/common/maas/dhcpd.conf
[2] https://i.imgur.com/eoICuaO.png