lxdbr0 does not get created automatically when setting up a LXD cluster using interactive command prompts

[tytus-kurek]

Required information

• Distribution:

ubuntu@cloud-1:\~$ uname -a
Linux cloud-1 6.8.0-48-generic #48~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Oct  7 11:24:13 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

• The output of "snap list --all lxd core20 core22 core24 snapd":

ubuntu@cloud-1:~$ snap list --all lxd core20 core22 core24 snapd
Name    Version        Rev    Tracking       Publisher   Notes
core20  20240416       2318   latest/stable  canonical✓  base
lxd     5.0.3-80aeff7  29351  5.0/stable/…   canonical✓  -
snapd   2.63           21759  latest/stable  canonical✓  snapd

Issue description

Setting up a LXD cluster using this how-to-guide works all fine when using preseed files:

ubuntu@cloud-1:~$ cat cloud-1 
config:
  core.https_address: 172.16.1.101:8443
  images.auto_update_interval: 15
storage_pools:
- name: default
  driver: dir
- name: my-pool
  driver: zfs
networks:
- name: lxdbr0
  type: bridge
profiles:
- name: default
  devices:
    root:
      path: /
      pool: my-pool
      type: disk
    eno1:
      name: eno1
      nictype: bridged
      parent: lxdbr0
      type: nic
cluster:
  server_name: cloud-1
  enabled: true
ubuntu@cloud-1:~$ cat cloud-1 | lxd init --preseed
ubuntu@cloud-1:~$ ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eno2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 5c:e9:31:f9:61:17 brd ff:ff:ff:ff:ff:ff
    altname enp1s0
    inet6 fe80::5ee9:31ff:fef9:6117/64 scope link 
       valid_lft forever preferred_lft forever
3: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether cc:96:e5:34:ff:e1 brd ff:ff:ff:ff:ff:ff
    altname enp0s31f6
    inet 172.16.1.101/24 brd 172.16.1.255 scope global eno1
       valid_lft forever preferred_lft forever
    inet6 fe80::ce96:e5ff:fe34:ffe1/64 scope link 
       valid_lft forever preferred_lft forever
4: lxdbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 00:16:3e:94:cd:de brd ff:ff:ff:ff:ff:ff
    inet 10.7.251.1/24 scope global lxdbr0
       valid_lft forever preferred_lft forever
    inet6 fd42:8c2:f182:3fa7::1/64 scope global 
       valid_lft forever preferred_lft forever

However, when using interactive command prompts instead, the lxdbr0 interface does not get created automatically:

ubuntu@cloud-1:~$ lxd init
Would you like to use LXD clustering? (yes/no) [default=no]: yes
What IP address or DNS name should be used to reach this server? [default=172.16.1.101]: 172.16.1.101
Are you joining an existing cluster? (yes/no) [default=no]: no
What member name should be used to identify this server in the cluster? [default=cloud-1]: cloud-1
Do you want to configure a new local storage pool? (yes/no) [default=yes]: yes
Name of the storage backend to use (lvm, zfs, btrfs, dir) [default=zfs]: zfs
Create a new ZFS pool? (yes/no) [default=yes]: yes
Would you like to use an existing empty block device (e.g. a disk or partition)? (yes/no) [default=no]: no
Size in GiB of the new loop device (1GiB minimum) [default=30GiB]: 30GiB
Do you want to configure a new remote storage pool? (yes/no) [default=no]: no
Would you like to connect to a MAAS server? (yes/no) [default=no]: no
Would you like to configure LXD to use an existing bridge or host interface? (yes/no) [default=no]: yes
Name of the existing bridge or host interface: eno1
Would you like stale cached images to be updated automatically? (yes/no) [default=yes]: yes
Would you like a YAML "lxd init" preseed to be printed? (yes/no) [default=no]: no
ubuntu@cloud-1:~$ ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eno2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 5c:e9:31:f9:61:17 brd ff:ff:ff:ff:ff:ff
    altname enp1s0
    inet6 fe80::5ee9:31ff:fef9:6117/64 scope link 
       valid_lft forever preferred_lft forever
3: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether cc:96:e5:34:ff:e1 brd ff:ff:ff:ff:ff:ff
    altname enp0s31f6
    inet 172.16.1.101/24 brd 172.16.1.255 scope global eno1
       valid_lft forever preferred_lft forever
    inet6 fe80::ce96:e5ff:fe34:ffe1/64 scope link 
       valid_lft forever preferred_lft forever

Steps to reproduce

Listed above.

[tomponline]

Hi @tytus-kurek

I think the reason is because you answered this way to the questions:

Would you like to configure LXD to use an existing bridge or host interface? (yes/no) [default=no]: yes
Name of the existing bridge or host interface: eno1

This will cause LXD to configure a macvlan NIC device in your default profile that connects to the host interface you specified (eno1).

If you answer no to the first question then LXD will try and configure a bridge called lxdfan0 if cluster wide fan networking is available.

Also is there a specific reason you're using LXD 5.0 (the previous LTS) rather than the current LTS which is LXD 5.21?