I’ve read several posts regarding daisy chaining routers etc., but did not see anything similar to my problem…I have 2 identical broadband routers (BEFSR41) each has it’s own separate external IP address that’s issued dynamically from my ISP, so I have the following setup:

Modem
|
Switch
____|____
| |
R1 R2
___|____ |__
| | |
PC1 PC2 PC3

I would like to bridge both routers so that I can share files…etc between both networks without installing a second nic in PC3 (if even possible). Keep in mind that both routers have/need their own external IP’s, so turning one router into a switch and disabling DHCP is not an option. Any ideas?

-Thanks

Sorry, spaces were stripped...

Modem
|
Switch
___|_____
| |
R1 R2
_|_____ |_____
| | |
PC1 PC2 PC3

Previous posts that recommended turning one of the routers into just a switch by disabling the routing features may not have involved two paths to the internet. Your scenario has the routers wired in parrallel and do not involve a wireless access point.

The following will work but since you didn't offer a little more information as to why you are trying to come up with a way to do what you are asking it may not be an option. It is more practical and secure.

Get another switch and connect the lan ports of both routers to it. Give each router's LAN interface a differnet IP address on the same subnet

router 1 - 192.168.1.1 /24
router 2 - 192.168.1.2 /24

All your computers will be configured with 192.168.1.x /24. The computers you want to use Router 1 will have Router 1 as their gateway in their TCP config. The computers that will use Router 2 will have Router 2 as their gateway.

another option is to replace those routers with others that can do a VPN between them.

The grass may not be greener on the other side . . . but it just might have less weeds. :-D

To give more background...I have a 3rd PC that is doing a lot of inbound/outbound requests and needs to run on its own external IP. I didn’t want to plug PC3 directly into the switch and use a software firewall, so I just used the second router I had lying around. So, current setup is as follows:

modem > switch
switch port 1 > R1 > PC1, PC2
switch port 2 > R2 > PC3

I could probably use one router for the entire setup without a switch by setting PC3 to a static IP, however my ISP does not issue static IP’s, just dynamic. Is there a better solution for this scenario besides spending some $$ on a new firewall/switch?

Also, given your previous suggestion, is it possible to connect both routers without using a second switch?

Using Puppet's method, you'll also need to turn off the DHCP service in each router and assign static IP info to each computer.

If both routers are using DHCP to serve dynamic IP info, you won't be able to ensure that a particular computer will always use the same router as its gateway.

This is my dilemma…I can’t assign a static IP to each machine because each external IP is dynamic. When I ordered a second IP from my ISP they couldn’t even tell me what the second IP would be. Also, if DHCP is disabled, doesn’t that effectively turn a router into a switch?

>> if DHCP is disabled, doesn’t that effectively turn a router into a switch?

No, it just means that you need to handle the IP assignments statically. Remember, you're connecting the modem to the WAN port and the computers go to the LAN ports and inbetween the router is using NAT to put the lan ports on a separate network (which is why you need to assign the IP's either statically or via dhcp.

Personally, I'd simplfy the setup by using only 1 router. Even though your ISP is giving you 2 public IP's, you are still connecting through the 1 modem connection. That is no different than them giving you 1 public IP and you having 2 (or more) computers behind 1 router. So, in your current setup, you gain nothing by using the 2 routers execpt a more difficult configuration and probably an added fee to your ISP which they're more than happy to charge you.

Keep in mind, the bandwith your ISP is giving you is per (modem) connection not per IP address. You only have 1 connection/modem.

>> I can’t assign a static IP to each machine because each external IP is dynamic.

That doesn't make sense. It doesn't matter if your public IP is static or dynamic, as long as your computers are behind the router, you can assign them their IP info either statically or dynamically via your router's dhcp server.

You could connnect the two routers without another switch. I should have noted that in my last post.
I checked the data sheet on that model router and it doesn't seem to have an uplink port nor a port that would autodetect another switch so you might need a crossover cable. Connect a patch cable, remember you might need a crossover cable, to a switch port on each router.

Fishmonger is right. You could have dynamic addressing asigned from your ISP for the WAN side but have static on your LAN. In this case you will need static addresses assigned to each computer to ensure proper gateway assignment.

The grass may not be greener on the other side . . . but it just might have less weeds. :-D

The main question to answer is why use 2 routers when 1 will do the job and be easier to setup?

Put everything in the switch.

Yes I have an uplink on both routers and putting everything in the switch without routers would not be very secure. If I were only to use 1 router, then all PC’s would have the same external IP, which I don’t want. Putting the switch between the modem and routers is the only way (that I know of) to get the second “dynamically” assigned external IP. BTW, yes I’m aware that I’m not getting any more bandwidth from the second IP . It’s crucial that PC3 has a different “external” IP than that of PC1, PC2. I already have all PC’s setup with static local IP’s (192.168.1.x). PC3 is making a large amount of requests to Google and even though I have an API key, Google puts me on their “crap list”; every time the API is running Google requires that I enter an image code every time I open a browser and do a web search…very annoying! This is one of the reasons for obtaining the second external IP, among others.

fyi, with the current setup, PC3 already has a different External IP than PC1, PC2…just need R1 and R2 to talk with one another. The second router is so that I don’t have to plug PC3 directly into the switch.

Using 1 switch, lets try this:

Connect the modem to the switch.

Connect the WAN port on each router to the switch.

Connect 1 LAN port on each router to the switch.

Connect all PC's to the switch.

If needed, configure port forwarding on R2 to PC3.

The routers should get their WAN IP info via your ISP's dhcp sever.

All PC's should have statically assigned IP info and all 3 are in the same subnet (i.e. 192.168.1.x/24). PC1 & PC2 should have R1 as their gateway and PC3 has R2 as its gateway.

>> PC3 already has a different External IP than PC1, PC2

Not exactly true. It's the routers that have the external IPs not the PCs.

Keep in mind that using that setup, you'll open up some security issues. If you want to maintain security, you'll need to use a 2nd switch on the inside (LAN side) instead of the 1 that is outside (WAN side).

Yes, you are correct, the routers have the external IP’s not the PC’s…I was just trying to convey that PC3 is making requests from a different external IP…

My current setup is already exactly how you describe except for 2 parts:

1. Connect 1 LAN port on each router to the switch
2. Connect all PC's to the switch (I assume you meant routers?)

I only have a 5 port switch (EZXS55W)

I connected LAN ports on each router to the switch and I was able to connect to a shared folder on PC1 from PC3, but this caused one of the routers to misbehave and the connection kept shutting off and on.

Thanks for all the input, but I think installing a 2nd nic in PC3 may be the best option since there doesn’t seem to be another viable solution.

I wouldn't do that when all you need is a crossover cable between the two router switches.

DONT connect routers wan and lan to a switch! That creates a loop and without engaging spanning tree you will shutdown your network.

So ISP to switch to routers 1&2. PCs to routers.
R1 has gateway of 192.168.0.1
R2 has gateway of 192.168.0.2
Assign the proper gateway to the pc

You can do static ip or dynamic with mac reservations. Either way you have;
R1 hosts 192.168.0.5-8 [4 addresses]
R2 hosts 192.168.0.10-13 [4 addresses]

No need for a second nic. Putting all devices on the switch defeats having a router(s).
You should answer the question of why is pc3 spamming google? Sounds like you have malware on pc3.

Give a person a fish you feed them for a day.
Ask a person to internet search and they learn a skill for a lifetime.

Yes, that is what was happening with whom ever made that last suggestion…routers were in a loop and the connection was shutting off and on…not good.

So I guess that’s the big question, how do you connect both routers with a crossover cable? What port to what port?

Also, PC3 is not spamming Google, well kind of  They know who I am and I’m aloud to make requests, I’m just on their default monitoring sys because of an API I’m running at my control.

Putting the LAN and WAN ports is absolutely the wrong thing to do.

Connect each end of the cross-over cable to any of the LAN (not the WAN) switch ports from each router.

Have all computers configured with static addressing and on the same private subnet, 192.168.1.0 /24 for example. Each computer's IP addresses should be unique.

Each desktop will use the gateway, Router 1 or Router 2, that you assign to it. You could then open ports accordingly on each router to permit whatever traffic you want to let through.

The grass may not be greener on the other side . . . but it just might have less weeds. :-D

Voila! All I needed was a cross-over. Thanks Puppet!

Your very welcome Zeus.

Somehow I just knew it would all work out for you. You seemed very determined.

Also, thanks for posting your results.

The grass may not be greener on the other side . . . but it just might have less weeds. :-D