Sharing host key across Rails nodes for Gitlab HA setup
I was helping a customer to setup Gitlab HA by following the documents at https://docs.gitlab.com/ee/administration/high_availability/README.html. We used F5 to do roundrobin balancing of SSH traffic on port 22. Before we copied over the host keys from the first Rails server to others we got error of offensive keys when git clone using ssh at every other request similar to #4398 (closed).
Suggest to at least mention the host key handling in the HA document. If it's not done at loadbalancer, the files in /etc/ssh need to be synced among all Rails servers with the proper mode。