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New Member

a Routing problem

we have three routers, mesh connected two of them has an ethernet interface and each interface is connected to a switch, the two switches must have the same IP subnet, how can we route traffic

8 REPLIES

Re: a Routing problem

Hi

L2 switches doesnt required to be address untill unless you have some plans for managing them remotely.

Otherwise they arent going to particpate in L3 forwarding at all..

i would suggest to post out ur topology (a schematic diagram) so that it will be helpful to understand how the connectivity goes thru...

also throw some lite on the ip scheme proposed to use out here in this scenario..

regds

New Member

Re: a Routing problem

we have servers on the Swithces 1 and 2 and they all must be in the same subnet 10.15.0.0/16 is that possible, and how will look the routing table in the router connected to SW3, how it is going to work??? we are using RipV2...

Re: a Routing problem

Hi

Can you revert whts the kinda connectivity between the routers ???

Are you trying this in ur lab setup or planning to put up in a live production network ?

regds

New Member

Re: a Routing problem

consider it at lab...but i dont know what is the diff. but it is okay consider at lab

Re: a Routing problem

Hi

With normal routing in place with RIPV2 and if u want to have the same subnet be used on both the LAN side i dont think thats gonna possible.

Probably u can think off using something inline with IRB technique..

Also u didnt mention about the interconnectivity of the routers ...

regds

New Member

Re: a Routing problem

you can connect the two switches by using ethernet cable (trunk if you have more than one vlan) to be in the same subnet, so you can give the two routers' interfaces IP addresses in the ssame subnet and any other router tries to reach the server will have two routes through the two routers and according to the routing protocol used it will prefer one link or it will loadbalance if their metric is equal.

Re: a Routing problem

Hi

(1)Why dont u try bridging between all the three routers.Its the easist way around.

(2)Rather more complex way is to do the routing, i.e, all the routers will have different subnets, but make a VPN tunnel between them and that will route your data.

Regards

JD

New Member

Re: a Routing problem

Hello: On the interfaces of the the routers that the switches are attached to is where your subnet will begin: all switches off that particular Routers' interface subnet will ARP the mac address of the switch and find the subnet;ergo, allowing the subnet to lead the frame to the correct switch.

e.g. R_1 int fa0/1 is 192.168.1.1 255.255.255.0___directly connected___to SW_1 int fa0/1

This allows the Arp to resolve the LAN addressing through Layer 2.

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