Saving ssh login details

http://rabexc.org/posts/using-ssh-agent

 

# Generate and encrypt the key first.
$ ssh-keygen 
Generating public/private rsa key pair.
Enter file in which to save the key (/home/test/.ssh/id_rsa): 
Created directory '/home/test/.ssh'.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/test/.ssh/id_rsa.
Your public key has been saved in /home/test/.ssh/id_rsa.pub.
The key fingerprint is:
ec:38:bc:94:35:34:55:2b:9a:8d:44:d8:f0:93:09:fb test@joshua
The key's randomart image is:
+--[ RSA 2048]----+
|      o+. ...    |
|      .=.+   .   |
|      . O . .    |
|       = B .     |
|        E .      |
|     . = .       |
|      * .        |
|     . o         |
|      .          |
+-----------------+

# Copy the public key to my remote server, conveniently called
# 'name-of-remote-server'. Note that it will ask you the password
# of the remote server.
$ ssh-copy-id name-of-remote-server
The authenticity of host 'name-of-remote-server (144.144.144.144)' can't be established.
ECDSA key fingerprint is 9f:1e:ab:b6:ff:71:88:a9:98:7a:8d:f1:42:7d:8c:20.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
Password:
...

# Try now to login into the remote server. SSH will now ask you
# for your passphrase, what you used to encrypt your private key on
# disk, what you gave to ssh-keygen above.
$ ssh name-of-remote-server
...

# Let's say you have multiple keys, or you decided to store your key
# in a non standard place, and want to provide a specific one for a given
# host, you can use the -i option.
$ ssh -i /home/test/.ssh/id_rsa name-of-remote-server

So… what are the advantages of using keys? There are many:

1. Your passphrase never leaves your local machine. Which generally makes it harder to steal.
2. You don’t have a password to remember for each different host. Or…
3. … you don’t have the same password for all hosts you connect to (depending on your password management philosophies).
4. If somebody steals your passphrase, there’s not much he can do without your private key.
5. If you fear somebody has seen your passphrase, you can change it easily. Once. And for all.
6. If there is a “man in the middle”, he may be able to hijack your session. Once (and well, feast on your machine, but that’s another story). If a “man in the middle” got hold of your password instead, he could enjoy your machine later, more stealthy, for longer, and may be able to use your password on other machines.
7. They just work. Transparently, most of the times. With git, rsync, scp, and all their friends.
8. You can use an agent to make your life happier and easier.