$ create_ssh_keypair.sh  user01  test-server-01

$ ./create_ssh_keypair.sh user01  test-server-01
Generating public/private rsa key pair.
Your identification has been saved in id_rsa.user01.test-server-01.
Your public key has been saved in id_rsa.user01.test-server-01.pub.
The key fingerprint is:
1b:97:af:30:66:11:e9:4e:30:e6:db:bc:f2:54:c3:a4 user01@test-server-01
The key's randomart image is:
+--[ RSA 4096]----+
|                 |
|         .       |
|      + o .      |
|     o + = .     |
|      . E *      |
|       * * o     |
|      . @   .    |
|      .+ + .     |
|       oo .      |
+-----------------+
==========================================================
Check
==========================================================

# ls -ltrh  id_rsa* |tail -n 2
-rw-r--r-- 1 fasthandle fasthandle  747 Dec 25 01:36 id_rsa.user01.test-server-01.pub
-rw------- 1 fasthandle fasthandle 3.2K Dec 25 01:36 id_rsa.user01.test-server-01

$FHHOME/fhscripts/create_ssh_keypair.sh

#!/bin/bash
#===============================================
# create_ssh_keypair.sh
#
# How to use
#     create_ssh_keypair.sh   user01  test-server-01
#===============================================

if [ "$#" -ne 2 ] ; then
    echo 'ERROR:  argument isn't correct.\'
    echo 'How to use:'
    echo 'create_ssh_keypair.sh  user01 test-server-01'
    exit 1
fi

USER=$1
HOST=$2

ssh-keygen -t rsa -b 4096 -C "${USER}@${HOST}"  -N "" -f id_rsa."${USER}"."${HOST}"


cat << @
==========================================================
Check
==========================================================
 
# ls -ltrh  id_rsa* |tail -n 2
`ls -ltrh id_rsa* |tail -n 2`
 
@