OPENVPN服务器下增加网络带宽流量控制

操作系统：CentOS Linux 4.x ( 2.6.9内核 )
VPN服务器：OpenVPN for Linux 2.0.x
VPN客户端：OpenVPN GUI for Windows 1.0.x

eth0 - 服务器外网网卡借口 ( 66.77.88.99 )
tap0 - 服务器VPN网卡借口 ( 10.8.0.1 )
VPN客户端IP: 10.8.0.2

要求：VPN客户端通过OPENVPN GUI软件连接到VPN服务器，然后通过NAT连接到外网，并对客户端进行流量限制．

*** 启动NAT

iptables -t nat -A PREROUTING -d 66.77.88.99 -j DNAT --to 10.8.0.2
iptables -t nat -A POSTROUTING -s 10.8.0.2 -o eth0 -j SNAT --to-source 66.77.88.99

*** 限制VPN客户下载速度为256Kbit/s

tc qdisc  add dev tap0 root handle 1: htb default 10
tc class  add dev tap0 parent 1: classid 1:1 htb rate 256kbit  burst 10k
tc filter add dev tap0 parent 1: protocol ip prio 16 u32 match ip dst 10.8.0.2 flowid 1:1

*** 限制VPN客户上载速度为128Kbit/s

tc qdisc  add dev eth0 root handle 2: htb default 10
tc class  add dev eth0 parent 2: classid 2:1 htb rate 128kbit burst 10k
tc filter add dev eth0 parent 2: protocol ip prio 16 handle 1 fw flowid 2:1
iptables -t mangle -A PREROUTING -i tap0 -s 10.8.0.2 -j MARK --set-mark 1
iptables -t mangle -A PREROUTING -i tap0 -s 10.8.0.2 -j RETURN