Hi some time back I asked this question and made a lot of changes to secure my system. Now I need to make a dummy account and give ssh access of this account to a friend. But I am unable to receive any incoming ssh connections. I can ssh to any server via my computer but can not ssh to even localhost. I am sure its due to some settings I changed in a bid to make my system more secure but know I don't remember those changes.
For one, I have disabled ufw. Also there is nothing blocking any user in /etc/ssh/sshd_config or in /etc/hosts.allow or /etc/hosts.deny.
I have attached the output of ssh -v localhost here. I narrowed down the problem to debug1: SSH2_MSG_SERVICE_ACCEPT received by comparing my output with this output on a friend's computer.
Edit 1: This is the output on using ssh -vvvvvv localhost
Any help is appreciated.
Best Answer
Try re-installing sshd with a purge:
The most probable root cause is a botched config in /etc/ssh/ssh_config. A purge would remove this file, and give you a blank slate, hopefully fixing your issue.