Loosing all my containers after upgrading from 1.2.0 to 1.4.0

Hello everyone,
I’ve get a little (big) problem today, I upgrade a RancherOS with the ubuntu console from 1.2.0 to 1.4.0 . This system was containing my Rancher 1.6.x server.
After the restart everything is empty … All my docks are vanish, my /var/lib/docker folder weight 132Ko.
I realy dont know what to do …

I have the same issue upgrading 1.3.0 to 1.4.0…
is it possible to upgrade without losing all installed containers ?

solution found