sshd is not installed by default on Linux Mint. To install:
sudo apt-get install openssh-server
Done!
tmux useful commands
tmux is a great alternative to screen if you’re looking for multiple virtual sessions in one terminal window.
Useful commands:
Ctrl-b c : open new session
Ctrl-b n | p : cycle next / previous through sessions
Ctrl-b % | ” : split horizontally / vertically
Ctrl-b left | right | up |down : cycle back /forward through visible split windows (left/right if split horizontally, up/down if split vertically)
Using Putty SSH, if you’re not getting line characters for the splits, change session charset to UTF8.
Disabling strict key checking on ssh
Key checking on ssh validates that the remote system you’re attempting to connect to is the same server that you connected to the last time, to help prevent the possibility that someone has hijacked the DNS name, IP, or the hardware itself.
However, some times you may want to avoid this checking. For example, I have a Raspberry Pi that I boot from multiple SD cards, but each is setup with the same IP. If strict key checking is enabled then your ssh client will prevent you from connecting when it detects a signature change. You’ll see this error:
RSA host key for 192.168.x.x has changed and you have requested strict checking.
To avoid this, edit or add ~/.ssh/config, and add:
Host 192.168.x.x
StrictHostKeyChecking no
where the IP can be the IP of the machine you’re connecting to, or you can use a * wildcard too (maybe not as secure).
If you’ve already connected and have a key in your known_hosts, then I think you need to delete this entry first, and then try with this config.
Removing a passphrase from an OpenSSH pub key
I’d set a passphrase on an OpenSSH key that I use to connect to a git repo on my local server. It started to get annoying, and more annoying with any other tool that I tried to use with the same key as it’s seems not all tools are setup to handle the prompting for the keyphrase.
Quickest workaround: remove the passphrase with ‘ssh-keygen -p’
– when prompted give the name of the pub/priv keypair (eg id_rsa), give the current keyphrase, and then when prompted for the new keyphrase, just hit return and again to confirm.