No internet connection, Repeater with wlan0/wlan1 setup.

[moryoav]

My issue: No internet connection, trying to set up a hotspot with 2 wireless networks (wlan0/wlan1).
I have an external USB wifi dongle, Raspberry Pi 4b.
I installed the Raspberry Pi OS prebuilt image, with nothing else (came with v3.30 of RaspAP).
I followed the instructions in the documentation:
https://docs.raspap.com/repeater/#configure-routing
Followed them to the letter, including changing the wlan0 metric number.
Everything looks fine, I can find the wifi network I want to connect to through the "WiFi client" and I can connect to it. However, in the networking screen I see wlan1, I see the IP address it got from the main router (192.168.1.100), the gateway is correct (192.168.1.1), but it says that there's no internet access (which can be verified once I connect to the Hotspot wifi network.
These are my logs and screenshots attached:
https://pastebin.com/YDg8Ji22
I tried restarting multiple times, reinstalling more than once, and I tried in a different home with different router and different internet, and I see the same result.
I feel like I'm missing something super obvious, something tiny I may have missed. If anyone can figure out what I missed, I'll really appreciate it...

[billz]

That's odd, your config looks okay. I'm connected to RaspAP in repeater mode with the same settings.

Your Networking panel is showing a connectivity issue with the gateway, which could indicate a problem with your upstream router and/or with the wireless adapter bound to wlan1. Try iw dev wlan1 link, ethtool -i wlan1 and check kernel logs with dmesg | grep -i wlan1. Once you get green check marks your repeater should be good to go.

Pro tip: if you want to restore RaspAP's default settings, System > Tools > Perform reset is faster than reinstalling.

[moryoav]

First, thank you so much for trying to help, I really appreciate it. I just hate it when things don't work... :-)
There are definitely strange things going on. Before trying your suggestions, I reset the device (from the menu + shutdown).
I decided to narrow it down and see how it works as AP with ethernet connected and the USB wifi dongle disconnected.
Reboot. I see the wifi network (RaspAP, back to the default name).

Bug #1: Although I did a reset, after connecting to the RaspAP, I'm in the UI at 10.3.141.1 and my username and password are the previous ones from before the reset and not the default ones (admin/secret). I expected that to reset as well. Make me suspect that maybe "reset" is not 100% resetting what it should, but I go on.

I then notice that I can correctly connect to the hotspot wifi network it creates (the password there has been reset to ChangeMe like it should). And I have internet (through Ethernet now).

Bug #2: I then change RaspAP hotspot name to the new name I want, I change the network to 5G instead of 2.4G and I change the password. I broke the device. I restart the hotspot. Now I don't see the network at all, the wifi hotspot is gone, I have no way connecting to the device.

I reflash the OS image. Again with the entire process, again with changing the hotspot network, again I don't see the Hotspot Wifi after restarting it. So I guess no 5G for me (I set the country code properly in the menu, if that's important information).

Back to factory reset. This time around I only change the hotspot name and password, without choosing 5G. Restarting the hotspot. This works. So the blame before was on the 5G network for some reason, I'm not sure why because yesterday I had no problem setting up a 5G network instead of the 2.4G, but that doesn't matter right now.

I keep the ethernet connected but I now plug in my wireless USB dongle.
lsusb shows the device is connected.
I go to WiFi client and I see networks to connect to. I choose the wifi network to connect to (also 2.4G network).
I go to DHCP Server and I give the metric for wlan0 a value of 3005 (not 305 like in the docs because for some reason wlan1 comes out to be 3004 and not 304).
Restart the hotspot.
This is what I see:

I have internet via the eth0, but not via the wlan1. Now to the commands you mentioned:

pi@raspberrypi:~ $ iw dev wlan1 link
Connected to 24:4b:fe:b7:10:f1 (on wlan1)
        SSID: juliaNet
        freq: 2412
        RX: 4210571 bytes (19293 packets)
        TX: 40116 bytes (590 packets)
        signal: -24 dBm
        rx bitrate: 130.0 MBit/s MCS 15
        tx bitrate: 65.0 MBit/s MCS 7

        bss flags:
        dtim period:    1
        beacon int:     100
pi@raspberrypi:~ $ ethtool -i wlan1
driver: rtw_8822bu
version: 6.6.74+rpt-rpi-v8
firmware-version: N/A
expansion-rom-version:
bus-info: 1-1.1:1.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no
pi@raspberrypi:~ $ dmesg | grep -i wlan1
[  458.268190] wlan1: authenticate with 24:4b:fe:b7:10:f1
[  458.268254] wlan1: 80 MHz not supported, disabling VHT
[  459.222076] wlan1: send auth to 24:4b:fe:b7:10:f1 (try 1/3)
[  459.224650] wlan1: authenticated
[  459.225777] wlan1: associate with 24:4b:fe:b7:10:f1 (try 1/3)
[  459.230037] wlan1: RX AssocResp from 24:4b:fe:b7:10:f1 (capab=0x1011 status=0 aid=16)
[  459.236122] wlan1: associated
pi@raspberrypi:~ $

Anything suspicious here?
A more general question, is it ok that I'm using both 2.4G networks, both on eth0 and on eth1? I read somewhere that on Raspberry Pi (maybe specific to 4B?) you can't have AP mode with 2.4G on both networks, one of them should be 5G, that's not correct?

Any further assistance will be highly appreciated...

Update: I decided to verify if it's perhaps the WIFI USB Dongle's fault. I switched with another one I had.
Now, I see a different result.

According to this I should now have internet!
So I go to SSH, I ping google, I see it pings successfully!
Now I connect to this network from a different computer on the network, and that device now does NOT have internet.
So the issue is somehow related to the connection of wlan0 to wlan1.

[moryoav]

I solved my problem with some ChatGPT help:
The solution was to type in ssh:
sudo iptables -t nat -A POSTROUTING -o wlan1 -j MASQUERADE

And that worked. Isn't that supposed to be part of the setup via GUI? Was I supposed to do something that would have enabled that and not via SSH?

[billz]

ChatGPT isn't quite right here. The application already handles this in two ways: 1) by enabling IP forwarding (sysctl -w net.ipv4.ip_forward=1), and 2) by applying masquerade NAT rules (below) to all outgoing traffic. It isn't necessary to explicitly define interfaces for this to work. The routing between them is handled by the Linux kernel's IP forwarding and the default routing table.

On my system, I simply connected an external adapter and repeater mode worked. I can't say for certain what the ultimate cause of your problems were, but a faulty/incompatible adapter seems to have been part of the problem (and a very common one).

# Generated by iptables-save v1.8.9 (nf_tables) on Thu Mar 20 10:53:12 2025
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
-A POSTROUTING -j MASQUERADE

[moryoav]

I ended up trying a 3rd adapter, this one is an old tplink I found in a drawer, something really old, that one worked out of the box immediately without any issues at all. So moving forward, I'll order one from the top list referred to in the docs.
One question remains though: is it ok to have 2.4ghz on both wlan0 and wlan1? I read somewhere that you're supposed to have 5ghz as the hotspot network. That's not the case? No issue with 2.4ghz on both?

[billz]

It's technically okay to operate two adapters on the same 2.4 (or 5) GHz band. Co-channel interference is more likely, but you can mitigate this by configuring them to use different channels (eg., wlan0 on channel1, wlan1 on channel 6 or 11).

[moryoav]

Ok, thanks for that. I guess we can close this for now. The big issue ended up in all likelihood the USB dongle, and I'll order a new one and hopefully it'll work well as well. The project is amazing, btw...

[billz]

Glad to hear you resolved it... and thanks for the kind words :)