Charm does not detect if the port it adds to bridge throws error

[Aymen Frikha]

Hello,

We had a case where we added OVS to a bond interface through bridge mapping config, but that bond already has a bridge connected to it with an ip address. This situation results in an error on the ovs port that can be detected when we use: ovs-vsctl show as follow:

 Bridge br-data-2
        fail_mode: standalone
        datapath_type: system
        Port bond2
            Interface bond2
                type: system
                error: "could not add network device bond2 to ofproto (Device or resource busy)"
        Port br-data-2
            Interface br-data-2
                type: internal

This error is not detected by the charm and I think it should be.