[chef] chef-server 11 migration

[Kirill Timofeev < >]

Folks,

I want to try chef-server 11. In order to do this I installed 
chef-server 11 and want to migrate some clients to it preserving 
certificates so that I could switch those clients back to old 
chef-server. I couldn't find any guidelines on migration and since 
server 11 uses postgress instead of couchdb I expect migration should 
have some peculiarities. May I ask you to share knowledge on this kind 
of migration?

Thanks,
Kirill.