I changed the hostname on my server before the DNS propagated, and when trying
to sign-in I got this on the client:

  ssh_exchange_identification: Connection closed by remote host

and in /var/log/auth.log on the server:

  fatal: Error initializing Globus Usage Metrics

and I was unable to login. If I had not kept an ssh session open I would have
been locked out of my server.

As soon as DNS propagation finished, verified by using dig on the server, I was
able to sign-in again with a new connection.

This could be an issue with vanilla ssh, but the error message makes it seem
like the cause is a failure in globus usage metrics, which should obviously not
be fatal and prevent sign-in. If it really is not a gsissh specific issue, the
"fatal" in the log message is very misleading.