ubuntu20.4 ssh不能连接问题

vi /etc/ssh/sshd_config
....
KexAlgorithms [e-mail],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1

最后添加一行，添加重启ssh服务就可以了
sudo systemctl restart sshd