I would like to be able to use ssh key to log into my web server via ssh and disable password authentication completely (to eliminate brute force from malicious ip addresses). So I am reading the documentation:

https://help.ubuntu.com/community/SSH/OpenSSH/Keys 

Now it instructs to do the following:

mkdir ~/.ssh

chmod 700 ~/.ssh

ssh-keygen -t rsa

Here's the problem with running ssh-keygen. I already did that in order to generate keys to connect to my github account. So my .ssh directory already looks like this:

~/.ssh$ ls -l

total 16

-rw------- 1 viggy viggy 1766 Sep  5 20:36 id_rsa

-rw-r--r-- 1 viggy viggy  403 Sep  5 20:36 id_rsa.pub

-rw-r--r-- 1 viggy viggy 4422 Dec 22 11:45 known_hosts

Will running that command again overwrite the id_rsa files? Is there a better way to store both keys?

My ultimate goal here is to not overwrite my git keys, yet generate a ssh public and private key so that I can copy the public key to ~/.ssh/authorized_keys on my web server.