$FHHOME/fhscripts/create_ssh_keypair.sh

$ create_ssh_keypair.sh  user01  test-server-01

$ ./create_ssh_keypair.sh user01  test-server-01
# ./key.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:
c3:b8:dc:ad:4d:28:98:14:64:c9:05:11:10:fc:ac:9a user01@test-server-01
The key's randomart image is:
+--[ RSA 4096]----+
| .o+**.          |
|  .oo            |
|   o.            |
|    o. o         |
|   .. . S        |
|  .. + o +       |
| o  o + o o      |
|E      . +       |
|        . .      |
+-----------------+
==========================================================
Check
==========================================================

# ls -ltrh  id_rsa.user01.test-server-01* |tail -n 2
-rw------- 1 root       root       3.2K Jan  1 01:04 id_rsa.user01.test-server-01
-rw-r--r-- 1 root       root        747 Jan  1 01:04 id_rsa.user01.test-server-01.pub

$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
cat << @
ERROR : argument isn't correct.
How to use:
  create_ssh_keypair.sh  user01 test-server-01
@
exit 1
fi

USER=$1
HOST=$2

OUTFILE=id_rsa."${USER}"."${HOST}"

test -f ${OUTFILE} && mv ${OUTFILE} ${OUTFILE}.`date +%Y%m%d_%H%M`
test -f ${OUTFILE}.pub && mv ${OUTFILE}.pub ${OUTFILE}.pub.`date +%Y%m%d_%H%M`

ssh-keygen -t rsa -b 2048 -C "${USER}@${HOST}"  -N "" -f ${OUTFILE}


cat << @
==========================================================
Check
==========================================================

# ls -ltrh  ${OUTFILE}* |tail -n 2
`ls -ltrh ${OUTFILE}* |tail -n 2`

@