Bonding in active-backup using linux bridges on Ubuntu 18
Because this was WAAYY more difficult to find any decent doco on that I had ever expected, here is what worked for me
I deleted the netplan config file at /etc/netplan/01-netcfg.yaml
1rm /etc/netplan/01-netcfg.yaml
Ensure that 'bonding' appears in /etc/modules (I's not here by default)
1echo bonding >> /etc/modules
Here is /etc/network/interfaces
1source-directory /etc/network/interfaces.d
2auto lo
3iface lo inet loopback
4
5allow-hotplug ens3f0
6iface ens3f0 inet manual
7bond-master bond0
8
9allow-hotplug ens3f1
10iface ens3f1 inet manual
11bond-master bond0
12
13allow-hotplug bond0
14iface bond0 inet static
15address 172.16.103.12/24
16gateway 172.16.103.254
17mtu 9000
18
19bond-mode active-backup
20bond-miimon 100
21bond-slaves none