ssh

普通登录

ssh -p 2211 root@140.206.185.170
# 使用默认端口22
ssh root@140.206.185.170

免密登录

先安装git

# 生成sshkey, 如果已经和github绑定过，则这一步不用执行
ssh-keygen
# 复制到目标服务器
ssh-copy-id root@192.168.0.106
# 等效于：cat ~/id_rsa.pub >> ~/.ssh/authorized_keys
# 重启服务
service sshd restart
# 登录
ssh root@192.168.0.106

修改ssh登录端口

vim /etc/ssh/sshd_config
service sshd restart

SSH心跳

sudo vim /etc/ssh/sshd_config
# 每30秒向客户端发送一次心跳
ClientAliveInterval 30
ClientAliveCountMax 6

登录异常

找不到host key

Could not load host key: /etc/ssh/ssh_host_rsa_key
Could not load host key: /etc/ssh/ssh_host_ecdsa_key
Could not load host key: /etc/ssh/ssh_host_ed25519_key

解决（生成key）：

sudo ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key
sudo ssh-keygen -t ecdsa -f /etc/ssh/ssh_host_ecdsa_key
sudo ssh-keygen -t ed25519 -f /etc/ssh/ssh_host_ed25519_key

没有权限登录

$ ssh alvin@172.17.163.113
alvin@172.17.163.113: Permission denied (publickey).

解决方案：配置密码可以登录。

sudo sed 's/PasswordAuthentication no/PasswordAuthentication yes/g' /etc/ssh/sshd_config