以下为校区ACM实验室多拨脚本，使用了macvlan模块，具体策略路由和连接标记等思路就不解释了。
#! /bin/bash
getip() {
ifconfig $ |grep -o -e 'inet addr:[^ ]*' | grep -o -e '[^:]*$'
}
ip link add link br0 address ::3e:aa:bb:xx dev veth0 type macvlan
ip link add link br0 address ::3e:aa:bb:yy dev veth1 type macvlan
ip link add link br0 address ::3e:aa:bb:zz dev veth2 type macvlan
dhclient veth0 veth1 veth2
iptables -t mangle -N PREROUTING_INPUT
iptables -t mangle -N POSTROUTING_GUESS
IPROUTE_ARGS=""
for((i=;i<;++i)); do
for ((j=;j<;++j)); do
IP="$(getip veth$i)"
[[ -n $IP ]] && break
sleep
done
[[ -z $IP ]] && continue
SUBNET="${IP%.[0-9]*}"
GATEWAY="${SUBNET}.254"
iptables -t mangle -A PREROUTING_INPUT -i veth$i -j MARK --set-mark $[$i+0x100]
iptables -t mangle -A PREROUTING_INPUT -i veth$i -j ACCEPT
iptables -t mangle -A POSTROUTING_GUESS -o veth$i -j MARK --set-mark $[$i+0x100]
ip route append "${SUBNET}.0/24" dev veth$i src $IP table default &&
ip route del "${SUBNET}.0/24" dev veth$i table main
ip route add default via $GATEWAY dev veth$i table veth$i
ip rule add from $IP table veth$i
ip rule add to $IP table veth$i
ip rule add fwmark $[$i+0x100] table veth$i
IPROUTE_ARGS=$IPROUTE_ARGS" nexthop via "$GATEWAY" dev veth"$i" weight 1"
done
# Connections can not change link, get link from saved mark, even for
# incoming traffic
iptables -t mangle -A PREROUTING -m conntrack --ctstate ESTABLISHED,RELATED -j CONNMARK --restore-mark
# Select link if not selected yet. NEW state can match conns even after reboot.
# Even for incoming connections destined to local address.
iptables -t mangle -A PREROUTING -m state --state NEW -j PREROUTING_INPUT
# Connection has no mark from PREROUTING, see which link is selected by routing
iptables -t mangle -A POSTROUTING -m state --state NEW -m mark --mark -j POSTROUTING_GUESS
# Save mark in conntrack when connection is created
iptables -t mangle -A POSTROUTING -m conntrack --ctstate NEW -j CONNMARK --save-mark
ip route replace default scope global table default equalize $IPROUTE_ARGS
# Remove default route from table main
ip route del default table main
# Add main table at top.
ip rule add from all lookup main