OpenWrt: PPPoE+DHCP Dual Access

WARNING! This is no longer needed on fresh builds of OpenWrt, which correctly handles DHCP+PPPoE using standard configuration means.

/etc/config/network
-----------------------------
config interface 'wan'
        option ifname 'eth1'
        option proto 'dhcp'

config interface 'wan2'
        option proto 'none'
        option ifname 'ppp0'
        option username 'LOGIN'
        option password 'PASSWORD'

/etc/config/firewall
-----------------------------
config zone
        option name 'wan'
        option input 'REJECT'
        option output 'ACCEPT'
        option forward 'REJECT'
        option masq '1'
        option mtu_fix '1'
        option network 'wan wan2'

/etc/hotplug.d/iface/30-pppoe
-----------------------------
#!/bin/sh
[ "$INTERFACE" = wan ] && {
        [ "$ACTION" = ifup ] && /usr/sbin/pppd \
                plugin rp-pppoe.so \
                mtu 1492 \
                mru 1492 \
                eth1 persist \
                usepeerdns \
                defaultroute \
                replacedefaultroute \
                user $(uci get network.wan2.username) \
                password $(uci get network.wan2.password) \
                lcp-echo-interval 5 \
                lcp-echo-failure 3 \
                unit 0
        [ "$ACTION" = ifdown ] && kill `ps | grep rp-pppoe | grep plugin | awk '{print $1}'`
}