ubuntu charm lacks lxc bridge config

[Liang Chen]

Current ubuntu charm doesn't provide any configuration options, so when deploy the following bundle in such a local env,

local env:
==============================
    local:
        type: local
        lxc-use-clone: true
        container: kvm

bundle:
==============================
sample:
  services:
    ubuntu:
      branch: lp:charms/ubuntu
      series: trusty
      constraints: mem=2G
      num_units: 1
      new-lxc-network: False
    mysql:
      to: lxc:ubuntu=0
      charm: "cs:trusty/mysql"
      num_units: 1
    wordpress:
      to : lxc:ubuntu=0
      charm: "cs:trusty/wordpress"
      num_units: 1
  relations:
    - - "wordpress:db"
      - "mysql:db"

the mysql and wordpress nodes will not have their network configured properly. Because by default lxc in the ubuntu instance uses dnsmasq to provide dhcp on lxcbr0, and the dnsmasq will choose a subnet that's different from the network that the ubuntu kvm instance is in.

It would be good to add a config option for the ubuntu charm, so that uses can choose whether to create a different subnet or just bridge to the exist network that the ubuntu instance is in for lxc containers.

[Antonio Rosales (arosales)]

@Liang,

Thanks for ensuring this Charm was also available for Precise. If you could please submit a merge proposal of your current branch, lp:~cbjchen/charms/trusty/ubuntu/lxc-network-config, against Precise we can test and then update the Ubuntu Precise charm.

While this is updated I'll put the status in "Incomplete" while you attach the Precise branch.

-thanks,
Antoino

[Liang Chen (cbjchen)]

Antonio,

Sure. Thank you for the help! I have just proposed the merged.

Thanks,
Liang

[Antonio Rosales (arosales)]

@Liang,

Pending a successful test this LGTM.

-Thanks,
Antonio