ssh
SSH Secure Shell, fix login problem from SSH Secure Shell to Ubuntu system
vim /etc/ssh/sshd_config
KexAlgorithms +diffie-hellman-group1-sha1
Ciphers +aes128-cbc
sudo service sshd restart
ssh with Public Key
ssh-keygen -t rsa, generate public key (id_rsa.pub) and private key (id_rsa) under /Users/lchen/.ssh directory
attach id_rsa.pub to .ssh/authorized_keys on the remote server
scp id_rsa.pub lchen@serverIP:.ssh
cat id_rsa.pub >> id_rsa.pub
Connecting to GitHub with SSH
Reference
Set up public-key authentication using SSH on a Linux or macOS computer
Algorithm Negotiation failed when trying to connect to server
