禁止默认情况下接收所有UDP流量

详解VPS开启UDP转发

在VPS（虚拟专用服务器）上开启UDP转发，可以实现将外部设备或网络上的UDP流量转发到VPS内部，方便监控和管理,以下是详细的步骤指南：

理解UDP转发的作用

UDP（用户数据报协议）是一种无连接的网络协议，常用于实时应用，如游戏、视频会议等，UDP转发允许将这些流量转发到VPS上,方便后续处理。

修改VPS配置文件

进入VPS的配置文件夹：

sudo cd /etc/vps configuration

找到vps.conf文件,添加以下内容：

[DEFAULT]
log_level = debug

这将启用详细日志输出,方便调试。

修改iptables规则

使用iptables规则表修改VPS的端口转发：

sudo nano /etc/iptables.ipv4规则表

添加以下规则：

添加以下规则：

# UDP转发规则
允许的源端口：80,443,22,21,23,255
允许的的目的端口：80,443,21,22,23,255
iptables -L -t state 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255

添加以下规则：

# UDP转发规则
允许的源端口：80,443,22,21,23,255
允许的的目的端口：80,443,21,22,23,255
# 源端口允许列表
src 80:80,443:443,22:22,21:21,23:23,255:255
# 目的端口允许列表
dst 80:80,443:443,21:21,22:22,23:23,255:255
# 添加NAT规则
NatRule: state 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255

添加以下规则：

# UDP转发规则
允许的源端口：80,443,22,21,23,255
允许的的目的端口：80,443,21,22,23,255
# 源端口允许列表
src 80:80,443:443,22:22,21:21,23:23,255:255
# 目的端口允许列表
dst 80:80,443:443,21:21,22:22,23:23,255:255
# 添加NAT规则
NatRule: state 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,198,1