On 17 Oct 2019, at 16:41, Steven Jones wrote:
ssh takes a long time to login but there is no load to cause this.
The first thing to suspect when logins take a long time with no tangible loading issues (i/o, memory, and CPU all good) is DNS. If your resolver is trying to query a non-responsive DNS server or servers but eventually hits one that works, login and anything involving email transport will be plagued by delays.
So: check /etc/resolv.conf and make sure all listed servers are responding to queries.