^{Home OS}

OpenSSH

Connecting to legacy servers

Symptom

Unable to negotiate with ADDRESS port PORT: no matching host key type found. Their offer: ssh-rsa,ssh-dss

Solution

Either specify the key algorithm via command line

-oHostKeyAlgorithms=+ssh-rsa

or add this option to ~/.ssh/config

Host ADDRESS
  HostKeyAlgorithms=+ssh-rsa

Do not enable dss if possible!

Refuse client locale

For server

Comment the following line in /etc/ssh/sshd_config:

AcceptEnv LANG LC_*

For client

Comment the following line in /etc/ssh/ssh_config:

SendEnv LANG LC_*

Connection sharing

Initial configuration

mkdir ~/.ssh/sockets
chmod 700 ~/.ssh/sockets

Host HOSTNAME
  ControlMaster auto
  ControlPath ~/.ssh/sockets/%r@%h-%p
  ControlPersist 600

Ending socket sharing before persist timeout

rm ~/.ssh/sockets/HOSTNAME*

Other

Generate private key

ssh-keygen -t rsa -b 4096 -C "comment"