[ILUG] Routing question

[Paul Jakma]

right..

this didnt make it through as an attachment, so lets try in-line. 
Below script sets up rules to look up ISP1 source-addr packets in 
table isp1, etc..

then all you do is set a multi hop default route in your main table.

--paulj


#!/bin/bash

# this script sets up ip rules to handle our dual ISP setup (ie make
# sure packets /not/ going to internal - hence going to internet - are
# sent via appropriate ISP)

#isp_nets - describe isps in form:
# tablename,ip-range,realm,gateway 
isp_nets="isp1,123.45.67.8/29,isp1-realm,123.45.67.9 \
	isp2,1.2.3.4/28,isp2-range,1.2.3.5"
intranets="192.168.0.0/16 10.0.0.0/8 172.16.0.0/12"
intrarealm=mycompany
pref=21000 

for prefix in $intranets; do  
	ip ru add to $prefix table main realm $intrarealm pref $pref ; 
	pref=$(($pref+100))
done

for net in $isp_nets ; do
	table=`echo $net | sed 's/^\(.*\),.*,.*,.*$/\1/'`
	prefix=`echo $net | sed 's/^.*,\(.*\),.*,.*$/\1/'`
	realm=`echo $net | sed 's/^.*,.*,\(.*\),.*$/\1/'`
	gw=`echo $net | sed 's/^.*,.*,.*,\(.*\)$/\1/'`
	#echo "$net: prefix: $prefix realm: $realm table: $table gw: $gw"
	ip ro add table $table default via $gw
	ip ru add to $prefix table main realm $realm pref $pref
	pref=$(($pref+100)) 
	ip ru add from $prefix table $table realm $realm pref $pref
	pref=$(($pref+100))
done