linux如何限制ip登陆

# 允许特定IP地址登录
AllowUsers user@192.168.1.100 user@192.168.1.101

# 或者拒绝特定IP地址登录
DenyUsers user@192.168.1.102 user@192.168.1.103

sudo systemctl restart sshd

# 允许特定IP地址访问SSH端口（默认22）
sudo iptables -A INPUT -p tcp -s 192.168.1.100 --dport 22 -j ACCEPT
sudo iptables -A INPUT -p tcp -s 192.168.1.101 --dport 22 -j ACCEPT

# 拒绝其他所有IP地址访问SSH端口
sudo iptables -A INPUT -p tcp --dport 22 -j DROP

sudo sh -c "iptables-save > /etc/iptables/rules.v4"

sudo apt-get install fail2ban

[DEFAULT]
bantime = 600
maxretry = 3

[sshd]
enabled = true
filter = sshd
logpath = /var/log/auth.log
port = ssh
maxretry = 3

sudo systemctl start fail2ban
sudo systemctl enable fail2ban

sshd: 192.168.1.100, 192.168.1.101

sshd: ALL