While playing around with Docker in my homelab, I was trying to get docker-compose to control another machine directly via contexts, instead of having to continually copy the compose file over and run it. However, I kept getting messages along the lines of
Secsh channel 10 open FAILED: open failed: Connect failed.
While its probably not the neatest solution out there, increasing the number of sshd connections seems to be a decent workaround. On Debian, the default is 10 which is probably adequate for most folk. However for me, this is too low.
The easiest way I have found to do this is to put the
MaxSessions 100 stanza required in a separate file called
/etc/ssh/sshd_config.d/10-maxsessions.conf which also has the advantage of being manageable by ansible. If the server needs rebuilt, I can run the playbook after a fresh install and the job is done for me.