Cache

The cache holds what the cluster's services share while they run, among it which BFF is active. Its role is named redis.

Where it is recorded

sudo xema node role add redis

This records which server holds it. It is recorded only: xema node apply never starts, stops or moves it, because moving it moves data with it. xema join and xema init set it up where it belongs.

xema node roles          # this server's roles, beside what is running
xema status              # every service on this server, running or not