eval "$(ssh-agent)"
export SSH_AUTH_SOCK=$(ls -t /tmp/ssh-**/* | head -1)
ssh-keygen -l -f /etc/ssh/ssh_host_ecdsa_key.pub -E sha256
ssh-keygen -l -f /etc/ssh/ssh_host_ecdsa_key.pub -E md5
or
ssh-keyscan localhost > localhost.ssh-keyscan
ssh-keygen -lf localhost.ssh-keyscan -E md5
or
ssh-keygen -r localhost
Port 9000 on remote machine mapping to port 22 on mine:
ssh -R 9000:localhost:22 me@remote
On remote destination put this at the end of file
Match User me
GatewayPorts yes
https://askubuntu.com/questions/50064/reverse-port-tunnelling#50075
ssh -J me@intermediate:1234 me@destination -p 5678