[atomic-devel] Docker-1.10 to docker-1.9 rollback.

[Daniel J Walsh <dwalsh redhat com>]

When you upgrade to docker-1.10, your container images json data gets
rewritten with UUID based on the content in the images.  This will take
a while, depending on the number and size of images.  One potential
problem is rollback. 

When I updated a docker to docker-1.10 (In devel, Rawhide) my images get
updated.  Now if I rollback to docker-1.9 I notice my containers are
disappearing.

docker ps -a
CONTAINER ID        IMAGE               COMMAND            
CREATED             STATUS                      PORTS               NAME
dc8ba4c69222        fedora              "bash"              13 minutes
ago      Exited (0) 13 minutes ago                       fervent_rosalind
1e1a4d59c375        fedora              "bash"              3 hours
ago         Exited (0) 3 hours ago                          amazing_yonath

Rollback to docker-1.9

[root dhcp-10-19-62-196 docker]# docker ps -a
CONTAINER ID        IMAGE               COMMAND            
CREATED             STATUS                      PORTS               NAMES

Nothing.

I create a container. (Using docker-1.9

I update to docker-1.10 again

docker ps -a
CONTAINER ID        IMAGE               COMMAND            
CREATED             STATUS                      PORTS               NAMES
6073b1c7c08f        fedora              "bash"              11 minutes
ago      Exited (0) 11 minutes ago                       boring_shockley
dc8ba4c69222        fedora              "bash"              13 minutes
ago      Exited (0) 13 minutes ago                       fervent_rosalind
1e1a4d59c375        fedora              "bash"              3 hours
ago         Exited (0) 3 hours ago                          amazing_yonath

Rollback to docker-1.9

[root dhcp-10-19-62-196 docker]# docker ps -a
CONTAINER ID        IMAGE               COMMAND            
CREATED             STATUS                      PORTS               NAMES
6073b1c7c08f        fedora              "bash"              13 minutes
ago      Exited (0) 13 minutes ago                       boring_shockley

Might be a bug, but this is something we need to understand in order to
figure out what happens if a atomic host upgrades and rolls back.