I have two 532's with R52s in each.
We are only providing Internet, and thus only want layer 3 traffic to pass between routers.
On Side A, we have a public IP on Ether1 (which goes to internet) and a private 192.168.70.1/24 IP on Wan1 which is in Ap Bridge Mode.
I have Nat Rule for Masq, out port Ether1
and a static route for 0.0.0.0/0 with a default gatway of my ISPs gw. (in same subnet as my public IP) Ether1 public IP
I have a static router for 192.168.190.0/24 with a GW of 192.168.70.2
On Side B
I set a private 192.168.70.2/24 IP on Wan1 which is in station Mode. and successfully connects to Side A, I can ping 192.168.70.1 just fine.
I have Nat Rule for Masq, out port Wan1.
I have DHCP server running on port Ether1 (which is uplinked to a switch) and which hands out private IP address in the 192.168.190.100-200 range. GW: 192.168.190.1
I also have a ip of 192.168.190.1 on ether1
NO BRIDGES ANYWHERE
This should work right? Just to provide internet to those 192.168.190.100-200 computers-
I had all this working and i've messed it up some how, as one night it quit working, but the wireless link is fine, so before i do a reconfig from scratch i want to make sure my layout is right.
if this is clean enough i'll submit to to the wiki as a layer 3 bridge as they already have a transparent WDS based bridge how to in there
Everything looks fine in this configuration.. One thing I believe is redundant is the multiple masquerading rules.
WAN: public IP
RouterA Routing table:
AS 0.0.0.0/0 ISP_GW
AS 192.168.190.0/24 192.168.70.2
DAC 192.168.70.0/24 <NULL>
Masquerading should be enabled on RouterA with a src-address of 192.168.0.0/16 (This will masquerade all networks including the routed ones as long as they using a 192.168.*.* subnet)
RouterB Routing Table:
AS 0.0.0.0/0 192.168.70.1
DAC 192.168.190.0/24 <NULL>
DAC 192.168.70.0/24 <NULL>
If you have masquerading enabled on RouterB you're doing NAT twice, which is unnecessary, but really shouldn't hurt anything. RouterB if the WAN interface is a wireless interface should be in "station" mode. As long as the correct routes are in place this will work fine.. Basic Networking/Routing 101.
You could do this without routing by using station-wds and transparently bridging the traffic. Whether or not that is a better idea depends on how many users you're dealing with and a few other factors.
It sounds like you may have an ARP issue, check to see that the arp entry in routerA still shows 192.168.70.2 mapped to the correct MAC address. It could be theres another device set to the same IP address. You could also create a static ARP entry on routerA so that it can't be overridden by another user.