Comment 4 for bug 1357357

We finally found a reason why upgrades fails sometime!!!

For some reason docker assigns same ipaddress for couple of containers, in this case this is astute and keystone.

[root@nailgun ~]# dockerctl shell astute
[root@442ed8aa3d43 ~]# ip a
155: eth0: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether ea:36:26:15:35:fb brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.8/16 scope global eth0

[root@nailgun ~]# dockerctl shell keystone
[root@00577252066e ~]# ip a
149: eth0: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 5a:47:c0:d0:bb:8b brd ff:ff:ff:ff:ff:ff
    inet 172.17.0.8/16 scope global eth0

But you can see that cached arp address is astute one

[root@nailgun ~]# arp -n
Address HWtype HWaddress Flags Mask Iface
10.108.20.1 ether 52:54:00:16:ed:ef C eth0
172.17.0.7 ether d6:fc:16:57:b4:4b C docker0
172.17.0.3 ether ae:1c:84:0a:da:3e C docker0
172.17.0.9 ether 8e:5b:68:a4:1e:ac C docker0
172.17.0.8 ether ea:36:26:15:35:fb C docker0

So this is why it failed