>> Your mistake with proxy_arp was probably the netmask for eth0 interface
>> or conflicting/missing routing for eth1 hosts.
>> Your eth0 should be configured with netmask 255.255.255.255, broadcast
>> same as IP, host route to the gateway on eth0, and default route to that
>> Then your eth1 could use the same IP as eth0, netmask 255.255.255.248.
>> Your public boxes on private side would use your eth0/eth1 IP as gateway.
>> echo 1 > /proc/sys/net/ipv4/conf/eth0/proxy_arp
>> Then it should work, with eth0 answering incoming arp requests for your
>> IPs on eth1. I am doing something similar with a /29 wireless subnet of
>> 18.104.22.168/32, host route to ISP gw, default to gw
I thought that IP refered you your eth0 IP, but on further examination and
details is actually your network IP, which on your ISP's modem/router's
internal side would be apparently .153/255.255.255.248 (to reach all your
IPs), if it has no way to set more specific internal routing.
The reason for 255.255.255.255 netmask on Linux eth0 is because only route
in that direction from Linux would be -host route to .153 and default gw
>> eth0 proxy_arp enabled
>> new Linux box
>> 8 port ethernet switch
>> | | |
>> .154 .155 .156
> No Joy. The GW is 153. Only an unused IP (157 or 158) can be used for
> eth0. Do you see what I've done wrong? (Do you need a description of
I do not know what WBTH/WGTFTH refers to.
>|# This does I/O and does not generate any errors.
>|# However, proxyARP doesn't work.
>|/usr/sbin/firewall.sh stop # Set Policy ACCEPT, Flush
>|ifconfig eth1 down
>|ifconfig eth0 down
>|ifconfig lo down
>|modprobe -r 3c59x
>|modprobe -r 8139too
>|ifconfig lo 127.0.0.1
>|ifconfig eth0 22.214.171.124 broadcast 126.96.36.199 \
>|ifconfig eth1 188.8.131.52 broadcast 184.108.40.206 \
>|ip route add 220.127.116.11 dev eth0
I am not familiar with "ip route", is that the same as "route add -host"
(ie, how does ip route know if adding a host or net route)?
Quote:>|route add default gw 18.104.22.168
Not sure if the ip_forward needs to be done before the proxy_arp (or if
>|echo 1 > /proc/sys/net/ipv4/conf/eth0/proxy_arp
>|echo 1 > /proc/sys/net/ipv4/ip_forward
>|# The above purportedly will answer arp requests for all IPs on eth1
>|iptables -A FORWARD -j LOG
> FWIW, 154 155 and 156 all use the same 'ifconfig eth1' and 'default gw'
> entries, identical except for IP. I "wrapped" the long lines for posting.
> "WBTH/WGTFTH" copyright the author. >
Can Linux reach all of the .153 gateway and .154 .155 .156? The only
thing I can think of offhand is if ip route is setting a net instead of
host route. But that should be easy enough to tell from route -n.