Firewall/NAT

Hello

Here my simple topology :

A modem/router "Linksys" with 192.168.1.254 as IP address connected to WAN interface of the Alix box with monowall.
WAN interface of monowall is 192.168.1.253
LAN interface of monowall is 192.168.1.100 and behind a switch with 3 clients.
Client IP address : 192.168.1.101 for exemple

Linksys 192.168.1.254 ==> Monowall WAN 192.168.1.253 ==> Monowall LAN 192.168.1.100 ==> Client LAN 192.168.1.101

From client, I can ping LAN monowall interface (192.168.1.100) but not WAN interface (192.168.1.253) .... so it is impossible to go on the web sure.

What can I configure ? Probably a route ... ?

thank you

System: Advanced setup >  Enable filtering bridge

Probably some Proxy ARP is needed

Enable filtering is active but no change.....

Maybe you just need to set your modem to "bridged" mode if possible? That will disable the router in it and then your m0n0wall is firewall/router.

Problem is not on the router linksys.
I must to ping WAN interface from the LAN interface, and I can't. It is before router linksys

What is the default rule of the monowall firewall ? Blocks all request ?