OpenSSH Server Day 14
The Secure Shell Protocol (SSH) is a network protocol for operating network services securely over an unsecured network.
OpenSSH is the connectivity tool for remote login with the SSH protocol.
Installing openSSH in both client and server machines
apt install openssh-server openssh-client
To check status of openssh
systemctl status ssh
Remote login from local machine
Disabling Root Login
Make configuration changes in /etc/ssh/sshd config to disable root login.
set PermitRootLogin to no
restart ssh to apply changes
systemctl restart ssh
Modifying default port to 2222 from 22
Make configuration changes in /etc/ssh/sshd config to change default port to 2222.
Allow/Deny users or groups
Make configuration changes in /etc/ssh/sshd config
No Password login with public/private rsa key pair
Generate key to login without password
ssh-keygen
Sharing Public key to enable Password less login
id_rsa is the private key
id_rsa.pub is the public key
copy key to remote server
ssh-copy-id -i id_rsa.pub -p 2222 kaniyam@remote_server
verify public key in remote server
Execute command from local/client
commands like touch, mkdir, and rmdir could be executed form local.
SCP command
Secured copy let copying of files to and from server to local