Comment 30 for bug 1532823

We can reproduce this issue with 100% chance. The problem is in this method https://github.com/openstack/fuel-nailgun-agent/blob/18289c69ffcb9a34208e51dd6a30de5178928e05/agent#L726-L743

How to reproduce:

1. Go to any operational environment

2. Pick a node, download network info:
fuel node --network --node 1 --download
cp /root/node_1/interfaces.yaml /root/node_1/interfaces.yaml.orig

3. Login to that node, edit /usr/bin/nailgun-agent and replace this line https://github.com/openstack/fuel-nailgun-agent/blob/18289c69ffcb9a34208e51dd6a30de5178928e05/agent#L737 with some hardcoded value, like:

            return {:ip => '10.110.2.4', :mac => '64:62:6c:0f:31:41'}

4. Download network info again and compare:
fuel node --network --node 1 --download
diff -U3 /root/node_1/interfaces.yaml.orig /root/node_1/interfaces.yaml

You can also find this log pattern in docker-logs/nailgun/app.log in such case:
2016-02-08 23:01:07.722 INFO [7f3969b2e880] (notification) Notification: topic: error message: Node 'node-4' has IP '10.109.9.5' that does not match its own Admin network '10.109.8.0/24'

Now we need to understand why nailgun-agent reports wrong info and fix it.