Generate Ssh Key Redhat 7

admin 09.12.2020

Red Hat Enterprise Linux 7 uses SSH Protocol 2 and RSA keys by default (see Section 12.1.3, “Protocol Versions” for more information). Important If you complete the steps as root, only root will be able to use the keys.
The Red Hat Customer Portal delivers the knowledge, expertise, and guidance available through your Red Hat subscription. Managing Public SSH Keys for Users Red Hat Enterprise Linux 7 Red Hat.
How To Create an SSL Certificate on Apache for CentOS 7 Updated January 4, 2017 562.6k views CentOS Apache Security. You can log in as your non-root user account through SSH and continue with the tutorial. Step One: Install Mod SSL. We did not create the key that is required to sign the certificate in a previous step, so we need to.
Apr 12, 2018 SSH, or secure shell, is an encrypted protocol used to administer and communicate with servers. When working with a CentOS server, chances are, you will spend most of your time in a terminal session connected to your server through SSH. In this guide, we’ll focus on setting up SSH keys for a vanilla CentOS 7 installation.

The Red Hat Customer Portal delivers the knowledge, expertise, and guidance available through your Red Hat subscription. Upload a public key —in this case, you generate the SSH key pair yourself and upload the public key to AWS (actually, the Fabric console commands will upload the public key for you).

am a new RHEL 8 server sysadmin. How do I configure SSH public key-based authentication for RHEL (Red Hat Enterprise Linux) 8 server?
Introduction – SSH is an acronym for secure shell. It is a suite of cryptographic network protocol. It allows users to log in and transfer files securely over the unsecure network such as the Internet. OpenSSH is an implementation of SSH protocol on RHEL 8. You can log in using RHEL 8 user and password account. However, OpenSSH project recommends log in using a combination of a private and public SSH keys.

Sample set up for our RHEL 8 server

Where,

You generate a key pair on your Linux/Unix/macOS desktop.
Place the public key on RHEL 8 server.
One can unlock public key using a private key stored on your desktop with the help of ssh command.
When both the public and private key correct you can log in without a password.

How do I set up SSH keys on RHEL 8 server?

The procedure to set up SSH key on Red Hat Enteprise Linux 8 server:

On your local desktop type:
ssh-keygen
Install public key into remote RHEL 8 server using:
ssh-copy-id user@remote-RHEL8-server-ip
Use ssh for password less login:
ssh user@remote-RHEL8-server-ip

Let us see all commands and steps in details.

How to create the ed25519 or RSA key pair

Matlab 2014 license key generator. The syntax is:
ssh-keygen -t ed25519 ssh-keygen -t rsa ssh-keygen -t rsa -b 4096 -f ~/.ssh/aws-lighsail.key -C 'My AWS SSH Keys' ssh-keygen -t ed25519 -f ~/.ssh/linode-usa-www1-vps.key -C 'My Linode SSH Keys for www'
Where,

-t rsa OR -t ed25519 : Specifies the type of key to create. The possible values “dsa”, “ecdsa”, “ed25519”, or “rsa” for SSH protocol version 2.
-b 4096 : Specifies the number of bits in the key to create.
-f~/.ssh/aws-lighsail.key : Specifies the filename of the key file.
-C -C 'My AWS SSH Keys' : Set a new comment.

I am going type the following command on my Ubuntu desktop to create the key pair:
$ ssh-keygen -t ed25519
I strongly recommend that you set up a passphrase when prompted.

How to copy the public key

Now our key paid generated and stored in ~/.ssh/ directory. You must copy a public SSH key file named ~/.ssh/id_ed25519.pub (or ~/.ssh/id_rsa.pub if you created RSA key) to the RHEL 8 server. Try the ssh-copy-id command as follows:
$ ssh-copy-id -i ~/.ssh/fileNameHere.pubuser@remote-RHEL8-server-ip
For example:
$ ssh-copy-id -i ~/.ssh/id_ed25519.pub vivek@192.168.2.211

How to log in using ssh and without a password

Now try logging into the machine, with the ssh command as follows:
$ ssh user@rhel-8-server $ ssh vivek@192.168.2.211
You should be able to log in without a password. If you set up a passphrase, unlock it as follows for your current session so that you don’t have to enter it every time you run ssh, sftp, scp, rsync and other commands:
$ ssh-agent $SHELL $ ssh-add

Optional settings for root user

Disable root user log in all together on RHEL 8 via ssh. Log in as root user on RHEL 8 and run following to add a user named vivek to wheel group:
# usermod -aG wheel vivek # id vivek
Allows users in group wheel can use sudo command to run all commands on RHEL 8 server. Next disable root user login by adding the following line to sshd_config:
# vi /etc/ssh/sshd_config
Disable the password for root login and only allow ssh keys based login:

Save and close the file. Reload the ssh server:
# systemctl reload sshd.service
For more info see “Top 20 OpenSSH Server Best Security Practices“.

Conclusion