Repeater in the same network - how?

Installing and Using OpenWrt
21

The 802N that you're using (assuming it is running the vendor firmware) is almost certainly running relayd and/or other possibly propriatary methods of achieving a similar goal. The point here is that the 802.11 standard does not support a direct bridge approach with wifi-sta > wifi-ap modes.

OpenWrt can achieve it using relayd, but this method isn't perfect and is kind of annoying to setup. Could it be better? Maybe, but it would require a lot of development work, especially given all the various target architectures it would have to accomodate.

Remember -- in the case of a commercially available device intended to be used as an extender/repeater, they have a single known architecture target, and therefore can put a lot of time and energy into getting it to work reasonably well; this is much much more challenging if you have to design a package (or set of packages) and/or method(s) for a huge variety of chipsets that each have their own quirks, as is the case with OpenWrt.

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So I am very confused why so many people are saying you can't do this or need relayd, I've been doing a version of this for years with different routers all running OpenWRT, but you'd need to install OpenWRT on your EAP6000 and it looks like it's supported.

Option 1: Basic Repeater
I'm basically going to just call out how to setup a dumb AP so search for those guides as they will probably help.

  1. On your EAP6000 login in to OpenWRT and navigate to Network -> Wireless and on radio of choice SCAN for the AP you want to connect the EAP to.
  2. Once connected you will need to create a matching SSID
  3. Follow Dumb AP instructions to set your LAN IP address in range of the network, set gateway to point to main AP or Server (which ever is doing DCHP), turn off DHCP and Firewall and then save and commit everything.

Option 2: Setup as Mesh

  1. Confirm that your devices will support (i forget how to check but you can google it) the WPAD-Mesh software on Openwrt. I just use the full "wpad-wolfssl" but wpad-mesh-wolfssl will also work. The EAP is ath79 so I think it will work.
  2. In Network -> WiFi you will need to add a Mesh interface (Mode = 802.11s) on both AP's and everything will need to match.
  3. Do all the Dumb AP setup and you should be good.
23

Have you tried doing exactly this? Can you share a config that is proven to be working based on this strategy without using relayd?

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I did. Since I'm a newbie on OpenWRT, I didn't find any settings for what I want.

Yep. Read further up, please, that's (Option 1) exactly what I had tried to configure umpteen times. Alas, to no avail.
I concede, that I didn't actually grasp OpenWRT; these interfaces, some LAN, some br, that you can delete, all sorts of things. No, despite of my best undertakings I didn't grasp the architecture.

The documentation is exhaustive, though for me not too well structured. So I didn't find a most simple client configuration; like if I wanted to just plug a printer into the Ethernet port. There was no simple 'client' option. I also missed the settings for nameservers on that same page; like what you usually see.
Whatever, whenever I had some client working (time was adjusted), and I added an AP, all client functionality was gone.

I'd be grateful - only if you have the time - to specify step-by-step? As an old networker, I do understand the relevant parts of it; only the UI seems to be in my way.

Thanks anyway!

Uwe

25

This is because of the limitations of the 802.11 standard... a wifi > wired (or wifi > wifi repeater) requires relayd or other 'hacks' to be supported.

I have difficulty believing that @CoffeyInOrlando 's option 1 can actually work -- I'd like to see the configuration as proposed and proof that it is working.

26

You wrote this before. Are we sure to talk about the same thing? I don't want to question your knowledge. Only, from 25 years in networking, I think I never came across any WiFi device that wouldn't work as a simple client. The USB dongles of 20 years ago did just that. Actually, I think I never came across any hard- or software that would do WiFi without a client functionality.
I mean, it doesn't make any sense to have any WiFi device (nor software) that isn't out of the box able to participate in a WiFi range as client. Does it? Okay, except an AP supplied via wired Ethernet. But even ALL those that at least I ever had in my hands, would also provide client functionality. If memory still serves me right.

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What do you want to see? I've done it half a dozen times or more.

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how make that work.
i do not think that is possible

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Sorry if there was some ambiguity in my earlier response.

  • Simple client, yes... no problem.
  • Routed client, no problem.
  • Bridge from wifi > ethernet (downlink) or wifi > wifi (repeater) doesn't work without either routing our relayd.

If you have a tested and working wifi repeater that doesn't use 802.11s, relayd, or routing (just wifi sta - wifi AP), which is what I interpreted as your option 1 statement above, I'd love to see how you did this. So this would mean looking at the config files (network, wireless, and possibly firewall and dhcp).

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I asked ChatGPT (version 2023-03-14) some questions. Here the conversation:

Me:

"Is it possible to make a "main router > wifi > repeater > wifi > client" configuration work with the OpenWrt software without having to use relayd or wds? If yes, how?"

ChatGPT:

		Yes, it is possible to configure a "main router > wifi > repeater > wifi > client" network topology without using relayd or WDS in OpenWrt.

		You can achieve this configuration using the following steps:

			1. Configure the main router as a regular wireless access point, and configure a separate subnet for the wireless clients.

			2. Configure the repeater to connect to the main router's wireless network, and bridge its wireless and Ethernet interfaces.

			3. On the repeater, create a new VLAN interface for the client network and assign it to the bridge.

			4. Configure the client device to connect to the new VLAN interface.

		Here's an example configuration using the LuCI web interface:

			1. Configure the main router:

			- Set up the wireless network with WPA2-PSK encryption and a separate subnet (e.g. 192.168.2.0/24).
			- Configure the LAN interface with an IP address in the main router's subnet (e.g. 192.168.1.1/24).
			- Enable DHCP server on the LAN interface.

			2. Configure the repeater:

			- Set up the wireless network to connect to the main router's network.
			- Create a new bridge interface (e.g. br-lan) and add both the wireless and Ethernet interfaces to it.
			- Create a new VLAN interface (e.g. vlan2) and assign it to the bridge interface.
			- Configure the VLAN interface with an IP address in the client network's subnet (e.g. 192.168.2.1/24).
			- Enable DHCP server on the VLAN interface.

			3. Configure the client device:

			- Connect to the repeater's wireless network.
			- Configure the network settings to obtain an IP address automatically (DHCP client).

		With this configuration, the client device should be able to connect to the Internet through the main router and the repeater, without using relayd or WDS.

(ā†’ Comment: Is this plausible? I personally have no experience with VLANs!)

Me:

How can I do "Create a new VLAN interface (e.g. vlan2) and assign it to the bridge interface."?

ChatGPT:

You can create a new VLAN interface and assign it to a bridge interface in OpenWrt using the following steps:

    Log in to your OpenWrt router's web interface (LuCI) or SSH into the router.

    Navigate to the "Network" section and click on "Interfaces".

    Click the "Add new interface" button.

    Enter a name for the new VLAN interface (e.g. vlan2) and select "VLAN" as the protocol. Click "Create interface".

    In the "VLAN ID" field, enter a VLAN ID number that is not currently in use on your network. You can use any value between 1 and 4094, but it's a good practice to use a number above 1000 to avoid conflicts with standard VLANs.

    Select the physical interface that the VLAN will be associated with (e.g. the LAN or WAN port on the router).

    Click "Save & Apply".

    Now that the VLAN interface has been created, you can add it to a bridge interface. Go to the "Network" section and click on "Switch".

    Under "Existing VLANs", select the VLAN interface that you just created (e.g. vlan2) and click "Edit".

    In the "Ports" section, select the bridge interface that you want to add the VLAN to (e.g. br-lan) and click "Add".

    Click "Save & Apply" to confirm the changes.

After completing these steps, the VLAN interface should be associated with the bridge interface and any devices connected to that VLAN should be able to communicate with the rest of the network.

Me: For "Enter a name for the new VLAN interface (e.g. vlan2) and select "VLAN" as the protocol. Click "Create interface".", I cannot find "VLAN" as protocol. Do I have to install a plugin for this?

ChatGPT:

If you cannot find the "VLAN" option under the protocol selection menu when adding a new interface, it's possible that the VLAN package is not installed on your OpenWrt router.

To install the VLAN package, you can SSH into your router and run the following command:

sql

opkg update
opkg install kmod-8021q

This will install the necessary kernel module and tools for VLAN tagging on your router.

Once the package is installed, you should be able to create a new VLAN interface by following the steps I outlined earlier:

    Log in to your OpenWrt router's web interface (LuCI) or SSH into the router.

    Navigate to the "Network" section and click on "Interfaces".

    Click the "Add new interface" button.

    Enter a name for the new VLAN interface (e.g. vlan2) and select "VLAN" as the protocol.

    Enter a VLAN ID number that is not currently in use on your network.

    Select the physical interface that the VLAN will be associated with (e.g. the LAN or WAN port on the router).

    Click "Save & Apply".

After completing these steps, you should be able to assign the VLAN interface to a bridge interface as needed.

Me: What other plugins are needed to make this configuration work apart from the default packages?

To make the "main router > wifi > repeater > wifi > client" configuration work with OpenWrt, you will need to install some additional packages in addition to the default packages that come with OpenWrt.

Here are some of the packages that you may need to install:

    wpad-basic or wpad-full: These packages provide support for wireless access points and clients, and are necessary for setting up the wireless interfaces on the main router and the repeater.

    relayd: This package provides support for relaying network traffic between two wireless interfaces, and is necessary for setting up the repeater interface.

    kmod-bridge: This package provides support for creating and managing network bridges, which are necessary for connecting the VLAN interfaces to the wireless interfaces.

    kmod-8021q: This package provides support for VLAN tagging, which is necessary for creating VLAN interfaces.

    luci-app-firewall: This package provides a web interface for configuring the firewall on your OpenWrt router, which you may need to modify to allow traffic to flow between the VLAN interfaces and the wireless interfaces.

You can install these packages using the following command:

opkg update
opkg install wpad-basic relayd kmod-bridge kmod-8021q luci-app-firewall

Note that the specific packages you need may vary depending on your hardware and configuration. You may also need to install additional packages depending on your network setup and requirements.

Me: Why do we need relayd?

ChatGPT:

Relayd is a package that provides support for relaying network traffic between two wireless interfaces. In the "main router > wifi > repeater > wifi > client" configuration, relayd is necessary for setting up the repeater interface.

The repeater interface works by connecting to the main router's wireless network, and then relaying traffic between the wireless clients connected to the repeater and the main router. Without relayd, the repeater interface would not be able to relay traffic between the wireless interfaces.

Relayd is also useful because it allows the repeater interface to use the same IP subnet as the main router's wireless network. This means that devices connected to the repeater interface will appear to be on the same network as devices connected to the main router's wireless network, and will be able to communicate with each other without any special routing or firewall rules.

Overall, relayd is an important package for setting up wireless repeater interfaces in OpenWrt, and is necessary for the "main router > wifi > repeater > wifi > client" configuration to work.

I was thinking of at least trying it, but i am running a snapshot build right now and cannot install another package without having to sysupgrade i think :smiley: So might take me a few days, if ever. I personally am curently using a relayd configuration.

PS: Here the OpenWrt docs about VLAN: https://openwrt.org/docs/guide-user/network/vlan/switch_configuration#vlan

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Me: is there not a way without relayd?

ChatGPT:

It is possible to set up a wireless repeater interface without using relayd, but it would require setting up the repeater interface as a router instead of as a bridge. This means that devices connected to the repeater interface would be on a different subnet than devices connected to the main router's wireless network, and would require special routing and firewall rules to communicate with each other.

Setting up the repeater interface as a router would also require assigning a different IP subnet to the repeater interface, which could potentially cause IP address conflicts if not configured properly.

In general, using relayd is the preferred method for setting up a wireless repeater interface in OpenWrt, as it allows devices connected to the repeater to appear as if they are on the same network as devices connected to the main router's wireless network. This makes it easier to configure and manage the network, and reduces the likelihood of IP address conflicts or routing issues.

Me: Teach me how to do the "main router > wifi > repeater > wifi > client" configuration by setting up the repeater interface as router insteaf of as a bridge.

ChatGPT:

Sure, I can provide a brief overview of how to set up a wireless repeater interface in OpenWrt using the router method. However, please keep in mind that this method is not the preferred method, as it requires more configuration and may lead to network issues if not set up correctly.

Here are the steps to set up a wireless repeater interface using the router method:

    1. Connect to the web interface of your OpenWrt router and navigate to the "Network" tab.

    2. Click on the "Wireless" sub-tab, and click the "Scan" button to scan for available wireless networks.

    3. Find and click the "Join Network" button next to the wireless network you want to use as the upstream network. Configure the wireless settings as necessary, including the wireless SSID, encryption type, and wireless password.

    4. Click the "Save & Apply" button to save the wireless settings.

    5. Navigate to the "Network" > "Interfaces" tab, and click the "Add new interface" button.

    6. Select "Static address" as the protocol, and enter a name for the interface (e.g. "wlan_repeater").

    7. In the "IPv4 address" field, enter an IP address that is on a different subnet than the main router's wireless network. For example, if the main router's wireless network is on the 192.168.1.x subnet, you could use the 192.168.2.x subnet for the repeater interface. Be sure to also enter the correct subnet mask and gateway IP address.

    8. In the "Physical settings" section, select the wireless network you configured in step 3 as the "Wireless Network" and select the wireless device that you want to use as the repeater interface.

    9. Click the "Save & Apply" button to save the interface settings.

    10. Navigate to the "Network" > "Firewall" tab, and click the "Add" button to add a new firewall zone.

    11. Enter a name for the new firewall zone (e.g. "zone_repeater") and select "Input" and "Output" as the "Zone forwarding" options.

    12. Select the "wlan_repeater" interface that you created in step 6 as the "Network" for the new firewall zone.

    13. Click the "Save & Apply" button to save the firewall zone settings.

    14. Navigate to the "Network" > "Firewall" tab, and click the "Edit" button next to the "zone_lan" firewall zone.

    15. In the "Inter-Zone Forwarding" section, select the "zone_repeater" firewall zone that you created in step 11 as a allowed zone.

    16. Click the "Save & Apply" button to save the firewall zone settings.

With these settings, the repeater interface will act as a router and relay traffic between the wireless clients connected to it and the main router's wireless network. However, devices connected to the repeater interface will be on a different subnet than devices on the main network, and will require special routing and firewall rules to communicate with each other. This method is not as simple or efficient as using relayd to set up a wireless repeater interface, so it is generally recommended to use the relayd method if possible.
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It is very plausible and highly likely there are mistakes in the guidelines provided by ChatGPT and maybe it is not possible after all, but it's very thoughtprovoking, to say the least, as this would be the first time I have seen a proposal to use VLANs for this type of setup.

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It was always possible to setup on different routed subnet

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You are right. I got sidetracked. The origional question in this topic is how to keep the clients in the same network.

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Like already mentioned the wifi standard does not support a true wireless repeater bridge (but 80211.s is maturing).

For a true wireless repeater bridge the packet needs to have three or more MAC addresses, the source the destination and the repeaters address.

Broadcom has its own proprietary WET) which works as a transparent arp relay, many vendors use relayd but there are true transparent bridges like WDS (or its successor Mesh 802.11s ), however WDS has no uniform implementation and is vendor and chipset specific, so it works only on select non Broadcom routers which are using the same exact chipset.

Newer chipsets support Mesh 802.11s but that is still a hit or a miss.

When using two R7800 (Qualcom Atheros) running OpenWRT (or DDWRT) you can use WDS which works without a problem.

That said pulling an ethernet cable or using Power Line adapters is my preferred way of connecting access points

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Donā€™t. Just donā€™t. The technology is fun, but it is just pulling from the internet and making human sounding responses. For any given question, it is not necessary correct, and it may state misinformation as if it were fact.

There are actual human experts on this forum. Yes, people make mistakes and may have incorrect information, too, but the discussions here will generally arrive at the correct answer even when that happens. Letā€™s not add unverified information from non human sources into the mix.

Use chatGPT and other AI tools if you want, but do so at your own risk, and donā€™t post the information here as if it were some authoritative source.

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37

Fair enough. Next time, i will test first, before I post.

I am aware, that ChatGPT often provides false and misleading information and hoped to have warned you all via

"It is very plausible and highly likely there are mistakes in the guidelines provided by ChatGPT and maybe it is not possible after all"

I think these language models like ChatGPT can be helpful though. The other day I asked it to format text from a .txt file as table so that I can import it into LibreOffice calc and it provided me with an even better solution, as it tought me how to import text from a .txt file into LibreOffice via LibreOffice specific table creating features. There were some small mishaps in it's answer, but nothing that prevented me from arriving at a workflow that was clearly working well. It mentioned features I have had no idea about before and that's because INDEED it takes informtion from the internet into account.

For future: all answers by ChatGPT require testing. Test first, then post.

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Better yet, donā€™t post results from ChatGPT. If you want to use it, thatā€™s fineā€¦ but donā€™t bother to post the answers it gives you hereā€¦ it doesnā€™t advance the conversation.

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This is the third time I see chatgpt taken as authoritative source of information in recent days on this forum - each time its responses were utter nonsense. I can only speak for myself, but the moment I see it being mentioned, I personally zone out of the thread - because, clearly, the AI is the new saviour of man kind and knows betterā€¦
Somehow I don't feel an urge to fight windmills.

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