OpenSSH Troubleshooting

Internal

• OpenSSH

Connection Takes a Long Time

In most cases this is caused by the server attempting to use DNS to get the IP name of the client. It is fixed by turning 'UseDNS' off. For more details, see:

Turn Off Client Name DNS Verification

Troubleshooting sshd Server

One method to troubleshoot a sshd server in an attempt to figure out why a specific ssh connection does not work as intended, is to stop the current sshd server (stopping the server won't drop the existing connections) and start it in foreground:

systemctl stop sshd

/usr/sbin/sshd -d [-D] [-d] [-d]