Is it possible to…? [multiple vlan wifi trunk]

Installing and Using OpenWrt
1

Hi there,

I am new to this forum and was hoping you guys could help me out.

I need to bridge my lan to another floor in the building. Running a cable isn‘t an option. Neither is powerline.

So I am looking at wifi. But here comes the problem: I need to transport at least 3 vlans together with my lan. As far as I know, normal wifi does not carry the vlan tags. Of course, I could set up a wifi bridge for each vlan separately. But I was wondering whether there is a smarter way.

So what I am contemplating is: hook up an openwrt enabled wifi access point to my lan. Set up another openwrt enabled access point on the other floor and put them in bridge mode. I am assuming that you can‘t bridge several ssids with one device (even if it supports several ssids in general) at the same time, or can you?

But let‘s say that doesn‘t work. Can I tunnel all the vlans that go into the one ap through a „normal“ wifi bridge and have them fall out at the other end (ap)? Can I do that with openwrt? And can I do that in particular with the APs I already have lying around, which are devolo wifi pro 1750s?

Thanks for reading!

2

Maybe one VLAN per WiFi SSID so this would be 4different WiFi:s to run 4 VLAN.

So the WiFi data itself has no VLAN ID but you give the data a new VLAN ID in the receiving AccessPoint

That works on my TP-link AP.

3

if both ends run openwrt(or mikrotik) eoip is an option(easy)... otherwise alternative tunnel methods can be used(harder)

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4

So you have two APs running openwrt that build a bridge and you bridge 4 ssids (one for each vlan) between them?

That would be the simplest solution in my view. Can you please explain how to set this up?

5

While I don‘t have Mikrotik, I do have openwrt.

And if it is easy, that sounds like a solution for me!

Could you please explain how to set up eoip between them in order to tunnel the four vlans?

Thank!

6

One possible solution would be running a GRE tunnel over wireless. A good description can be found at https://badgateway.qc.to/vlans-and-wifi/ Works perfectly. Be careful if you try this out, there is an error in the config files on that page. Better use those from GitHub as a starting point.

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7

I haven’t tested the hypotises with a reciever, that in technical terms is a radio link system and not a WiFi. And they exist for ethernet distribution.
But business class access point have the ability to have different VLAN connected for Tx and Rx to different SSID both on 5 and 2,4GHz.
It must be posts about this on this forum somewhere already, have you tried searcing?

8

No, each STA can only connect to a single AP.

9

I did exactly this some time ago, using GRE tunnels. I created a post with step-by-step instructions.

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10

I've used batman-adv for this but it is probably way overkill compared to eoip or GRE.

2 Likes
11

My AP can link different ssids to separate vlans. But I would need to set up four receivers, one for each ssd.

Unless it is possible to use one that would connect to all four ssids simultaneously and link them again to vlans. This is what I understood your suggestion to be. But I now take it that you haven‘t actually put this into practice.

1 Like
12

(Deleted - sorry, did not read your post carefully enough).

13

I am also using batman-adv here which is easy if once setup as you just have bat0.(vlanId) interfaces to add to your bridge device on each AP participating in the batman-adv mesh. Also offers the advantage to add more than two routers if you like to.

AP1:
bridge 1 - mgmt vlan 10
members: eth0.10, bat0.10, wlan1 (mgmt ssid)

bridge 2 - guest vlan 20
members: eth0.20, bat0.20, wlan1-1 (guest ssid)

AP2:
bridge 1 - mgmt vlan 10
members: eth0.10, bat0.10, wlan1(mgmt ssid)

bridge 2 - guest vlan 20
members: eth0.20, bat0.20, wlan1-1 (guest ssid)

14

For a network that is two points or a one hub and spokes, it should also work to put batman-adv on top of an AP-STA link (instead of mesh mode on the radio), but I have not actually tried that.

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15

Can you link to that post please ?

16

I have done this with Cisco AP's several times. I would think you could just create the WLAN interfaces on both sides and tag the vlans you want to pass through accordingly. Maybe I'm oversimplifying it, IDK.

17
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18

Hello and sorry for hijacking this post and thread. I was wondering, if you still use this tunnel setup. I have read the other thread and it's clear, and I intended to use the examples mentioned, however in the recent OpenWrt releases, there are some changes, mostly about DSA, and some UCI naming conventions. Might be possible to have a write-up adjusted to the recent situation? I have tried the same with VXLANs, but apparently it is not possible to bridge tagged interfaces with this protocol.

19

Sorry, but I moved the trunk to a cable, before DSA.

20

Gotcha, less of a headache for sure :slight_smile: