Creating Key Pairs For Terraform Use

Description

Sometimes, you will need to create a key pair, deploy a VM, and then add that key to the Authorized Hosts. Here is how:

To Resolve:

1. Create keypair for a new user:

   cd c:\scripts
   mkdir keys
   cd ./keys/
   ssh-keygen -t rsa -m PEM -b 2048
   

2. Take public portion and add it to your variables:

   variable "ssh_authorized_keys" {
   type        = string
   description = "ssh authorized key"
   default     = "ssh-rsa AAAAB3Nza..D0RiVG6Wz7oisRN81Xu4iraxN"
   }
   

3. Run the terraform apply to provision the VM.

4. Next, you should be able to ssh to the machine and add other keys as needed.

   gerry@home:C:\scripts\keys
   > ssh  -i key cloud-user@10.97.4.205
   The authenticity of host '10.97.4.205 (10.97.4.205)' can't be established.
   ECDSA key fingerprint is SHA256:E5vsJ6oDFIZxG+AvQaxxEqZ9Ck8b8IBKBBSASBrxfpA.
   Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
   Warning: Permanently added '10.97.4.205' (ECDSA) to the list of known hosts.
   Activate the web console with: systemctl enable --now cockpit.socket
   
   Register this system with Red Hat Insights: insights-client --register
   Create an account or view all your systems at https://red.ht/insights-dashboard
   [cloud-user@my-vm ~]$
   [cloud-user@my-vm ~]$ sudo su
   [root@my-vm cloud-user]#
   [root@my-vm cloud-user]# whoami
   root
   [root@my-vm cloud-user]#
   [root@my-vm cloud-user]# cat /etc/redhat-release
   Red Hat Enterprise Linux release 8.7 (Ootpa)
   [root@my-vm cloud-user]#
   

5. Here we create a new local user and add some public portion of a key pair to authorized_keys file:

   useradd myuser
   mkdir /home/myuser/.ssh
   echo ssh-rsa some-key >> /home/myuser/.ssh/authorized_keys
   visudo # add : %myuser ALL=(ALL) NOPASSWD: ALL
   chown -R myuser:myuser /home/myuser/.ssh
   

6. In Windows, to connect to a newly deployed VM you will need to use the SSH Keys you just created. Here is how you do it, for example, connecting to the my-vm in previous steps:

7. First, get the private key and paste it in a file called priv.txt at c:\scripts.
   • Now right click on the file and “disable inheritence” and “convert all permissions to explicit”.
   • Then remove everyone except your user and give your user full rights to the file.

8. Now ensure you have the Windows SSH Client feature installed, Add-WindowsCapability -Online -Name OpenSSH.Client~~~~0.0.1.0

9. Next, open Powershell and cd to that directory and use the key file to connect to a VM:

   cd c:\scripts
   ssh -i priv.txt cloud-user@10.10.10.10