mykb - A collection of random software
General
The basic syntax is
ssh user@domain
You can either log in using a password or an ssh key. The second method is considered safer and more user friendly. To initialize the ability to log in using an ssh key, you need a local ssh key-pair. If you dont have one, generate one on your local machine using
ssh-keygen -t rsa
and following the instructions. This generated a public and private
key pair which are saved in ~/.ssh
. To then enable the key
based login, you have to make sure that ~/.ssh
exists on
the server. Change the permisions of this folder using
chmod 700 ~/.ssh
. The next step is to make the
authorized_keys
file using
touch ~/authorized_keys
chmod 600 ~/.ssh/authorized_keys
Now open the authorized_keys
and copy-paste the public
key contents in to it.
One can also use ssh-copy-id user@domain
after
generating the key-pair.
Add keys to Keychain
If you added a passphrase to your key, you may be tired of typing it
over and over again. Add the following to your
~/.ssh/config
.
Host HOME
User root
HostName domain.example
IdentityFile ~/.ssh/id_rsa
AddKeysToAgent yes
UseKeychain yes
This saves the passphrase in the keychain for the current session. It
also allows you to specify which specific key to use and to use
ssh HOME
to connect to the server.
Add keys for layered logins
If you need to connect to an access server before connecting to the actual server you want to connect to, this can be automized by adding
IgnoreUnknown AddKeysToAgent,UseKeychain
All EXEMPLUM-COMPANY
Host EXEMP*
User username
IdentityFile ~/.ssh/id_rsa
AddKeysToAgent yes
UseKeychain yes
Access server
Host EXEMPaccess
HostName login.example.com
Working server
Host EXEMPwork
HostName work.example.com
proxycommand ssh -CW %h:%p EXEMPaccess ## access server
to your ~/.ssh/config
. To connect to the working server,
just type ssh EXEMPwork
.