Authenticate SSH user with FreeRadius Server

1. add EPEL repository
yum -y install pam_radius

2. vi /etc/pam.d/sshd
auth       required     pam_radius_auth.so

3. mkdir /etc/raddb
vi /etc/raddb/server
your_radius_ip your_radius_secret 3

useradd username

on FreeRadius Server:
add this server to NAS table
add ssh username and password

Notes:
use ansible to add users:

yum -y install ansible openssh-clients
ssh-keygen -q -t rsa -f ~/.ssh/id_rsa -C ‘‘ -N ‘‘
ssh-copy-id remote-ip-address

vi /etc/ansible/hosts

add single user:
ansible all -a "useradd username"

add multiple users:
vi /root/createuser.sh
#!/bin/bash
for username in username1 username2 username3; do
id $username > /dev/null 2>&1
if [ $? -gt 0 ]; then
   useradd $username
fi
done

chmod +x /root/createuser.sh

ansible all -m script -a "/root/createuser.sh"