Adduser to ssh into Aws Ec2-CodePudding

I am testing to setup a Git on the Server (Ec2 - Linux Amazon). All things are going fine but I did one thing that I can not reproduce and I would like to understand.

I am following this tutorial for Git on the Server https://git-scm.com/book/en/v2/Git-on-the-Server-Setting-Up-the-Server

I created 4 users to test and created their ssh key on server. (User Git) On /home/git/.ssh/authorized_keys file, I added the other 3 users public key (id_rsa.pub) to allow them push.

I use this commands to create users and ssh keys. I checked all permissions on /home/username/.ssh folders (700) and authorized_keys (600) file.

$ sudo adduser git
$ sudo su - git
$ cd
$ mkdir .ssh && chmod 700 .ssh
$ touch .ssh/authorized_keys && chmod 600 .ssh/authorized_keys

I created ssh key on ec2 using the following commands

$ ssh-keygen -o
or
$ ssh-keygen -t rsa -m PEM

My question is, why one user I can ssh into ec2 using public-key (id_rsa.pub)? The other 3 users I only can ssh into ec2 using private key (id_rsa)

I am ssh into ec2

$ ssh -i username.pem [email protected]

Thanks

CodePudding user response：

The other 3 users I only can ssh into ec2 using private key (id_rsa)

Double-check that using, with one of the three users:

ssh -Tv [email protected]

You will see exactly what ssh is using for its connection.

"They are effectively interchangeable.": John alluded to the fact:

ssh needs to send the public key to the remote user
the public key can be derived from the private key (at least, in practice)
therefore, you can use one or the other.