Generating an SSH keypair in Linux on CREODIAS
In order to generate an SSH keypair in Linux, we recommend using the command ssh-keygen.
If system does not see this packet installed, install the latest updates:
- Ubuntu and Debian family
sudo apt-get update && apt-get install openssh-client
- CentOS and Red Hat
sudo yum install openssh-clients
After that, use the following command in terminal:
ssh-keygen
with additional flags:
- -t
rsa authentication key type
- -b
4096 bit length, 2048 if not specified. Available values: 1024, 2048, 4096. The greater the value, the more complicated the key will be.
- -C
user@server name for identification at the end of the file
- -f
~/.ssh/keys/keylocation location of folder with ssh keys
- -N
passphrase, can be omitted if user prefers connecting without additional key security
![../_images/ssh1.png](../_images/ssh1.png)
Application will ask for the name of the key. Press Enter for defaults:
id_rsa for private and
id_rsa.pub for public key and passphrase (pressing Enter ignores it).
![../_images/ssh2.png](../_images/ssh2.png)
Next, ssh-keygen will show
location, where the keys are saved,
fingerprint of keypair and certain
semi-graphic image as expression of randomness in generating unique key.
![../_images/ssh3.png](../_images/ssh3.png)
To avoid problem with rejecting files due to too open permissions, navigate to the folder containing both keys and enter command:
chmod 600 id_rsa && chmod 600 id_rsa.pub