[millerm]

I'm trying to set up a repeater-bridge, but I need the repeater to take care of it's own clients' DHCP because the parent network keeps assigning new IP's every time a client swaps nodes.

Repeater non-bridge breaks port-forwarding because of double-NATing.

Help?

(P.S. sorry for lack of detail, the forum said error click back and lost my long, detailed post so I really don't want to re-type everything)

[matt0401]

There's no need to worry about the repeating router needing to assign separate DHCP addresses. Once you've got it set up as a repeater bridge this will be a non-issue. The roaming wireless clients will keep their IP addresses assigned by the DHCP server on the primary router and everything will work fine in the background.

To configure a router as a repeater bridge:

- Go into the "Setup" tab and give your router a distinct IP address to avoid IP address conflicts between the primary router and repeater. It is logical to use 192.168.x.n+1 where x is the subnet and n is the address of the primary router. Click "Apply Settings".

- Go into the "Wireless" tab and under the "Basic Settings" area, set the "Wireless Mode" to "Repeater Bridge". Click "Apply Settings".

- Under the "Wireless Physical Inferface wl0" area, set the SSID to that of the primary router. This tells the repeater to connect to the primary router to find the original signal. Click "Apply Settings".

- Click on "Add" under the "Virtual Interfaces" area on that page. We'll be adding the signal that will be repeated here. Create a name for the repeated signal. Choose a new SSID to allow wireless clients to choose which signal to connect to, or use the same SSID as is being repeated to allow clients to automatically roam. Click "Apply Settings".

- Go into the "Setup" tab and under the "VLANs" area, check all of the boxes to the right of "Tagged". This will unlock the rest of the boxes. Check all of the boxes to the right of 0 and 1. Make sure the drop boxes under "Assigned To Bridge" have "LAN" selected. This step links the LAN segments between the original signal and the repeated signal, enabling all traffic to pass seamlessly through. It should look like the diagram below.


- The setting of the router to "Repeater Bridge" should have automatically completed certain steps, such as disabling WAN and the DHCP server on the repeating router. If for some reason it hasn't, disable these in the "Basic Setup" area of the "Setup" tab.

Finished! Repeater bridges are one of the most powerful things you can create using DD-WRT. They are infinitely-scalable (only limited by IPv4) and allow you to create controlled mesh networks with automatic roaming. It is worth noting, however, that it places additional strain on the routers' radios. There are already two wifi connections being made and the fact that it's a repeater cuts through bandwidth in half. For heavy file transfers, an AP + Client Bridge combo would help maintain through bandwidth, and a traditional wired connection is always superior to any wifi link. But for internet use, repeater bridges can be very useful.

To take advantage of this scalability, apply this tutorial to a 3rd (or 4th, 5th, and so on) router, treating the 2nd router as the primary router and the 3rd router as the repeater. Any repeated signal can also be repeated again by more repeaters in the network. If you are using more than 2 routers in this type of system, using distinct SSID's will help keep things organized in terms of the routers linking up properly. The repeaters will connect to the strongest signal with the SSID they are configured to connect to. If the repeaters don't have a clear choice as to which of the other routers to connect to, the network won't be as stable, with the routers constantly re-aligning their links among each other. The diagram below illustrates this. The situation on the left will allow for a common SSID and roaming without the routers getting confused. The situation on the right will not, and distinct SSID's should be used among all routers.

[millerm]

Maybe you have a suggestion why it's not working right then. My setup has one parent router (older Belkin 54G) and one DD-WRT repeater (Netgear WG602).

It works flawlessly until the parent runs out of addresses in it's DHCP pool (192.168.2.2-192.168.2.100) which shouldn't happen with only a few clients. My repeater was set static IP 192.168.2.250 so it shouldn't have caused conflicts. I have this same problem (described below) on Windows XP, Windows Vista, Windows 7, and Windows Mobile.

Here's an example:
1. turn on computer and it connects to the repeater, the Belkin parent router gives it the first available address (192.168.1.2)
2. walk toward the parent node, it roams and is re-assigned a new IP (192.168.1.3)
3. walk back toward the repeater and it roams again, gets another new IP (192.168.1.4)

Also, power-cycling a client connected to the parent access-point it will get the same IP back, BUT power-cycling a client connected to the repeater it will get a new IP. I first found this when my smartphone crashed the system because every 5 minutes it woke up to download email (via wifi) it was assigned the next available IP address, in under an hour nothing was responding.

This continues until the DHCP client table on the Belkin router is filled and the router locks up, and the client can't get an IP address.

I can't replace/modify the parent router because it's no longer under my control. I made a deal with the neighbor when I graduated college I gave them all my wireless stuff and set it up secured with WPA2 for free, in exchange I get free internet for the cumulative few weeks per year that I'm visiting my relatives down there.

I hoped DD-WRT would have some way I could work around this issue, I think the Belkin router is mis-interpreting the MAC of the repeater as being the client instead of reading the forwarded DHCP request (not sure how that all works).

I know how it *should* work because my parents have Verizon FiOS and I set up a WRT54G-TM as a repeater, it doesn't exhibit the strange behavior nor do two other DD-WRT repeaters I've build for friends. But throw a Belkin 54G in as the parent and logic goes out the window.

Any other suggestions?

[millerm]

Also, maybe someone with the forums can explain why I keep getting "Error an attempt to automatically insert text blah blah" and it deletes my reply when I click back? Fortuniately, I copied my reply to Notepad so I didn't lose everything this time.

[ReadtheAnnouncements!]

Read the announcements at the start of this forum. The solution to your issue is likely there, and if it isn't information that you need to post, which you haven't is outlined. The instructions that were posted by Matt0401 were incomplete. Use the better instructions in the wiki.

The announcements also tell you how to deal with that "mistake...." that you get when you take too long to post.

[millerm]

[matt0401]

Ah, I see now. I had an incomplete understanding of your problem. I didn't realize that you had no control over the DHCP server on the primary router. It is possible that settings on the primary router are interfering with the ability of the clients to maintain their assigned addresses. I have never encountered this problem, so I wouldn't know where to begin addressing it on the primary router. Given that you have no access to it, I'll ignore it, and think of a new solution.

What we need to do is exactly what you originally thought. We need a second DHCP server on the repeater. It is possible to configure this on one router and have everything work properly, but I've never done this and so I cannot provide instructions without first experimenting with my own setup to determine how it can best be done.

Instead, what I'd like to do is test to see if this will work at all. You mentioned having a spare router. Set the DD-WRT router we would have used as a repeater as a "Client Bridge" instead, and have it connect to the primary router. Attach a cat5 cable between one of the LAN ports on the client bridge and then plug this into the WAN port of the Belkin spare router you had. Enable the DHCP server on the Belkin router and use it as normal. These are going to be on different subnets so there's no need to worry about gateways or IP address conflicts.

If this works, then in the future you can tinker with settings on the DD-WRT router to get everything working by using software, rather than hardware as we're doing with this test. It is possible to route everything behind the scenes so that it's repeating a signal, though it's on a different subnet with its own DHCP server.

[millerm]

[matt0401]

Actually if you want everything in the same subnet then the repeater bridge I described is what you're after. I don't understand what's causing your DHCP problem, where roaming forces the DHCP server to assign a new address but it will need to be fixed in order to have that seamless roaming. Repeater bridge will put everything on the same subnet. Repeater will allow you to break them up into different subnets with separate DHCP servers.

Replacing the primary router with something running DD-WRT might help a lot. We can make sure there is a proper DHCP server running. I understand this may be difficult, but it'd probably help you out a lot.

[millerm]