Migration from Swarm to Swarm Mode

Hi All.

I have existing docker Swarm (old mode of work for docker 1.6 till 1.12) setup with docker 1.13 underneath. As a storage plugin devicemapper is used, my operating system is RHEL 7.3 x86_64. I would like to migrate it to new swarm mode with docker community edition 17.03.

I have some questions:

  1. Is there a need usually to remove before upgrade and recreate after upgrade all running containers? Or will docker after an upgrade start all containers without much hassle?

  2. What is the proposed storage driver for docker for RHEL 7.3? From my experience devicemapper has its flaws and I wonder if currently there are other options for RHEL.

  3. Any general things which I should take care of?

Thanks for all info.

BR,
Rafal.