/admin/shutdown is supposed to perform a clean shutdown i.e. wait for all pending requests to complete, do a snapshot and then shutdown the server. It’s the preferred way to perform a shutdown though even killing the server is not an issue. It is only used to shutdown a Dgraph server instance and not the cluster. We don’t have a similar command for Zero yet.
Yeah, for now all admin commands are only allowed from localhost though Added IP whitelist for admin/export by armcburney · Pull Request #2233 · dgraph-io/dgraph · GitHub is adding support for whitelisting of certain IPs.