How to do a SSH authentication without password

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Introduction

Each time you want to connect to an external server you need your password... You're tired? I propose a method to avoid having to enter password.

To do this we will use the == SSH key == type RSA or DSA.

Principle is simple:

• You create an encrypted SSH key on the local computer (local)
• You send a part of it to the distant server (for example kimik2)

Create a SSH encrypted key on the local machine

The key is composed of two file: id_dsa and id_dsa.pub.

• id_dsa is the private key!!! DO NOT DIVULGE !!!
• id_dsa.pub is the public key.

First, check if you have or not this key. It is located in the .ssh directory

/home/user_local/.ssh/

If there is already this two file, go to the last part of this tutotial, else let's create this files. It is very easy via the keygen function:

ssh-keygen -t dsa

The computer ask you: Enter file in which to save the key (/home/user_local/.ssh/id_dsa): I let this part empty Then the computer ask you for a passphrase. Of course you have to put one for your security.

If everything is OK, the 'echo' is: Your identification has been saved in /home/user_local/.ssh/id_dsa. Your public key has been saved in /home/user_local/.ssh/id_dsa.pub. The key fingerprint is: 7b:53:c3:.................:e8:6c:bb user@local The key's randomart image is: +--[ DSA 1024]----+ | | | | | | | . . | | S ++.o | | . +o+++ | | . +oo +=.| | . .+o=. | | .E+...| +-----------------+

--construction--