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-   -   Running Second Router in Router Mode: DD-WRT (

des_a 04-09-2018 02:32 AM

Running Second Router in Router Mode: DD-WRT
Hello. I was troubleshooting here:, and I needed to know how to get my routers working without NAT, so I can give things another go. Sometimes, double NAT, is a bad idea anyway. Some people say ALWAYS.

If I do everything exactly the same, but set my router to "router" mode, instead of "gateway" mode, which disables NAT, it does not work. I need help making this work.

All my routers, are now running DD-WRT. Probably no longer the latest version, but I'll try to upgrade soon, but not necessarily now. They might work better after upgrading.

I'm thinking, I need to create a VLAN in the first router and do something like that. But I'm not exactly sure if that's true or not. Plus, I don't know how to create VLANs or anything, or really, what they are, which is what's stopping me from trying that theory. I prefer to do everything possible from the web interface. Please help. Thanks!

P.S. - This doesn't seem to be exactly the same problem, or solution, but it's awfully close:

jefro 04-09-2018 01:06 PM

Most routers running alt firmware can be set in one of 4 modes.

There is not much of an issue running double nat by the way. I have done it for decades.

If your version of dd is able and your hardware is able then you can set it to any mode. A few of them will seem to lock you out since it will no longer accept input to the web interface.

What tutorial did you use from the dd web site?

des_a 04-12-2018 01:57 AM


What tutorial did you use from the dd web site?
Actually... I didn't even know they had tutorials. Via click and point method, where are they on the website? I'll look, and see if I can find them, if not, I'll need help. Maybe tutorials will help me figure this out...

So, the "larger" picture, of what I'm trying to do, is get airprint to work on ipads, without breaking what already works. Something about either needing to be in the same subnet, or needing to be not NATed to work. Something about broadcasts not working all over the place or something. I don't quite get it yet, so I'm experimenting.

Anyway, I know it doesn't work in my situation, the way things are. I thought that running without NAT would be better. So running without NAT is the smaller picture of what I'm trying to do. I would like to try this for now, without breaking anything else, even if it doesn't help, and even if I decide it doesn't benefit me, and want to change it back afterward. I should learn to do this.

The theory, is that I should have all second routers (or maybe most of them), in router mode, and not gateway mode. However, it doesn't work for some reason. That was why I double NATd it. Except for the Windows Sharing issues and the airprint issue, I haven't had any issues with double NAT. I solved the Windows file sharing issue, I think. Now I'm trying to see if I can solve the airprint issue, which is going to require to try to put things in router mode, and see what happens. So I want to learn what is necessary on the first router, to make it work on the rest of the routers. All the routers are running DD-WRT. I will upgrade them soon as well, if there is upgrades available for them, to see if that fixes my small stability problem on clientrouter.

So my first step should be looking at tutorials on DD-WRT, so I'll give that a try, and see if that works or not. I'll tell you here, what I learned, or that I still need help finding them. Thanks!

des_a 04-12-2018 02:05 AM

Looks like I've found what "appears" to be the tutorials, you were talking about. Whether or not it is, it's worth taking a look at. Unfortunately, it looks like they only refer to the latest version of DD-WRT. So I'm going to upgrade now, and try to see what the new firmware is like. I "could" be offline while I upgrade the firmware...

des_a 04-12-2018 02:24 AM

So I've upgraded 2 out of 3 routers now. I've upgraded every router but guestrouter. That's because guestrouter is a different model. So it can wait until later.

It looks like it was new enough already, that there are no new features on the surface or anything. But hopefully, there's been some changes under the hood, that will make clientrouter more stable as it runs.

I'll take a look at what I "believe" are the tutorials you were talking about now.

des_a 04-12-2018 02:41 AM

Unfortunately, in the place I'm looking, anyway, I don't see a tutorial for what I'm trying to do. I'll link to the tutorial section, I'm looking in:

I see some tutorials for connecting two routers wirelessly, but I want to connect them in the wired way. I would like to use the WAN port and not trick it by using the LAN port if it would easily work that way. In other words, I really don't want to have to change the physical connection to anything. I'd like to try and make all the changes that are necessary in mainrouter, and have things "just work" when I set it to router mode in clientouter, or if I wanted, in guestrouter. Also, any other router, for that matter (at least as long as it's dd-wrt).

I'm thinking it has something to do with either some kind of bridge, or the VLAN options. Neither of which, I know how to use right now. I would play with them, but I don't want to break things so that it won't work from not first understanding what I'm doing, before I make a change.

des_a 04-12-2018 02:51 AM

P.S. - The reason I want to connect them in a wired way, is both because they are close enough right now, that it's silly not to, and because that is my standard based off of the way things work right now, and the technology I can afford to make things work. This has to do with the fact that at times, I'm basically sending large "images" over the network, back and forth. I use Clonezilla-SysResc CD, to boot from System Rescue CD, and create partimage images, which I send over the network (but without a partimage server). These either are patterns, or backups. I use them so that when something goes wrong, I can either re-install the latest backup image, or re-create it from the proper pattern. These things are stored on mainnas.

I have used it thus far after getting setup to work, recently for fixing problems with my servers. So far, I believe I've had to redo vmain at least once. I've had to redo 3 app servers this way before too. Then, I've had to backup the vweb server, so that I could see if my fixes made it work. So far, my fixes worked, so now I have a good backup for when it fails again. Hopefully, things will go smoothly, and nothing will fail anytime soon, but just in case, now I have my images and stuff. mainnas, is one of the more important servers that I have right now.

des_a 04-12-2018 02:53 AM

P.P.S. - mainnas is important because, in what is currently an Active Directory free network, it provides features that Active Directory also provides. Active Directory is overkill for now, and is only Windows based, I think. But I have some of it's features that ARE useful, on Windows and Linux, by using mainnas.

des_a 04-12-2018 02:55 AM

P.P.S. 2 - mainnas also does other functions, such as storing most software for me, as well. This includes OS install disk ISO images.

des_a 04-12-2018 01:56 PM

Looks like this:, is actually the same problem with setting my router to router mode.

I did see one place linked to from there, which showed me how to set the router to router mode: But I don't know if that is what I want or not. First, I think, I would like to try keeping the individual subnets, but diabling NAT. Then, I'll see whether or not the airprint will work. If it doesn't, the next best is to try this, except for having DHCP on this router act like the DHCP for everything connected wired or wirelessly to it, and then have a non-conflicting DHCP router on mainrouter as well, even if they are in the same subnet. Only the advanced instructions, "might" work for me.

des_a 04-12-2018 01:56 PM

Please give me feedback, and tell me if I'm at least on the right track or not.

jefro 04-12-2018 03:12 PM

Totally lost now.

Do you simply want to use router as a downstream switch?

des_a 04-13-2018 02:10 PM


Do you simply want to use router as a downstream switch?
I don't know what a downstream switch is. But I do know what a switch is.


I don't know exactly what you call this, but I would like to try these solutions:

1) Behaves as a type of router, connected to mainrouter, as it already does, but with no NAT. Clients behind the router, on mainrouter, have a subnet, and are served by mainrouter for DHCP. Clients behind clientrouter, have their own subnet. All communication can be passed between both subnets, back and forth. They just have two separate address spaces. clientrouter serves it's address space with DHCP. Everything gets through to everywhere, except for it somehow "stops" at the router and is translated in a way that makes it compatible with the new subnet. Wireless is on the same subnet.

If I could get this, I'd try airprint and see if it works or not. If it works in this configuration, and nothing else is browken, great! If it doesn't, or this is somehow an impossible communication with DD-WRT, then, I'll move on to the next thing.

2) Behaves as a kind of an access point/router/switch/combination. There is a subnet that mainrouter is on, and clientrouter is on that subnet too. Wireless clients are on the same subnet, as well. For now, it's too small to care if this HAS to be the results or not. clientrouter serves DHCP to it's clients, without getting in the way of mainrouter's clients, which it serves DHCP to.

As always, I need to have only clientrouter's MAC locked down in mainrouter to have all MACs in clientrouter enabled on clientrouter, but clientrouter needs all it's own MACs to enable clients to connect to it. Each IP will continue to be static, unless it's a temporary guest on the network, which I have specifically enabled access to.

Hope this helps you help.

des_a 04-13-2018 02:10 PM

P.S. - I don't want to have to physically connect it differently.

des_a 04-13-2018 02:12 PM

VLAN Information I found that might help me:

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