SSH Server On CentOS7

ssh

Basic Command

install

dnf install -y openssh-server openssh-clients
systemctl start sshd
systemctl enable sshd
firewall-cmd --permanent --add-service ssh
firewall-cmd --reload

/etc/ssh/sshd_config

vim  /etc/ssh/sshd_config

19:#ListenAddress 0.0.0.0
49:PermitRootLogin yes
55:#PubkeyAuthentication yes
79:PasswordAuthentication yes


systemctl reload sshd
systemctl status sshd

Keyauthen

สร้าง key ให้แก่ user ในที่นี้สร้าง key ให้แก่ user admin

su - admin
ssh-keygen -t rsa -b 4096
ls ~/.ssh/

ssh remote login with key

copy public key ไปยัง targetserver (จับคู่แลก ip)

su - admin
    ssh-copy-id   -i ~/.ssh/id_rsa.pub  admin@ip_targetserver
ssh admin@ip_targetserver

บนเครื่อง Target Server

vim  /etc/ssh/sshd_config

PasswordAuthentication no
PubkeyAuthentication yes

restart

systemctl restart sshd