OpenWrt Support for Asus RT-AC88U

@arinc9 @patient0
I tried @patient's build, but there is no change...no connection with guest WiFi, regular WiFi is working well.

Here is you can find my config with modified passwords:
backup-AP_QU-2021-10-05.tar.gz
login: root
password: admin123

Would be great if you can check it on your router.

@scatman75 Do I understand correct that there's a DHCP server for 192.168.5.0/24 but it's not this OpenWrt box for you?

And where does the guest network get it's IP from? Also from an external DHCP server?

@patient0
You figured it out right. The gateway for both VLANs is an OPNsense software router that also offers DHCP as a service for both VLANs. The ASUS is just one of the APs on the network.
VLAN 1: 192.168.5.0/24 -> GW 192.168.5.1, DNS 192.168.5.1
VLAN 3: 192.168.190.0/24 -> gw 192.168.190.1, DNS 192.168.190.1

@scatman75 : ok, I have to see how I can replicate that.

Your OPNsense box is on port 1 I assume. Do you get an IP address from the VLAN 3 range on port 3?

I would guess that is more a problem with VLANs than WIFI - but it's really just a guess.

On port 1 only VLAN 3 is tagged, VLAN 1 is untagged. I assume you untag VLAN 1 on the OPNsense box? This would make VLAN 3 the only tagged traffic.

@patient0
First of all, thank you for your efforts to help me.

Port 1 is the uplink port to a managed switch. This switch is connected to the main switch which is connected to the OPNsense router.

I got an IP address with kernel 5.4 alias arinc9s version (21.02), while connecting a laptop to port 3. I haven't tried it with kernel 5.10 alias the current master.

You're right. VLAN 3 is the only tagged VLAN on this AP. There are a total of 5 VLANs (Main, Guest, IoT, Entertain, Wan) on the main switch and the other two APs.

I'll try your build (5.10 with Wireguard) and plug a laptop into port 3 to see if it can get an IP address of the desired IP range.

Well, I ran the test by connecting a laptop with @patient0's firmware to port number 3. As expected, the laptop has received an IP address of the correct subnet, see the picture of the Macbook below.

Next up is @arinc9's v5.15 image.

I dusted off my APU2 with OPNsense on it and configured a VLAN3 on the LAN1 port. LAN1 of APU2 is connected directly to LAN1 on ASUS RT-AC88U. That should simulate @scatman75's setup for testing.

On LAN3 I get an IP from the 192.168.190.0/24 range correctly with either OpenWrt 21.02 with kernel 5.4 or the newer images with 5.10 or 5.15 - as @scatman75 did too.

Guest WiFi only works on 21.02 with kernel 5.4, it doesn't work with either kernel 5.10 or 5.15.
On my Linux Laptop the log hint that there's a timeout while trying to get an IP from the DHCP (see below, third to last line).

Oct 07 10:25:21 xps-9550 wpa_supplicant[754]: wlp2s0: Associated with 4e:ed:fb:9f:12:39
Oct 07 10:25:21 xps-9550 wpa_supplicant[754]: wlp2s0: CTRL-EVENT-CONNECTED - Connection to 4e:ed:fb:9f:12:39 completed [id=0 id_str=]
Oct 07 10:25:21 xps-9550 wpa_supplicant[754]: wlp2s0: CTRL-EVENT-SUBNET-STATUS-UPDATE status=0
Oct 07 10:25:21 xps-9550 kernel: IPv6: ADDRCONF(NETDEV_CHANGE): wlp2s0: link becomes ready
Oct 07 10:25:21 xps-9550 NetworkManager[2739]: <info>  [1633595121.7753] device (wlp2s0): supplicant interface state: associating -> completed
Oct 07 10:25:21 xps-9550 NetworkManager[2739]: <info>  [1633595121.7753] device (wlp2s0): Activation: (wifi) Stage 2 of 5 (Device Configure) successful. Connected to wireless network "Home_Qu_L1"
Oct 07 10:25:21 xps-9550 NetworkManager[2739]: <info>  [1633595121.7754] device (p2p-dev-wlp2s0): supplicant management interface state: associating -> completed
Oct 07 10:25:21 xps-9550 NetworkManager[2739]: <info>  [1633595121.7755] device (wlp2s0): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
Oct 07 10:25:21 xps-9550 systemd-udevd[2992]: regulatory.0: Process '/sbin/crda' failed with exit code 255.
Oct 07 10:25:21 xps-9550 NetworkManager[2739]: <info>  [1633595121.7811] dhcp4 (wlp2s0): activation: beginning transaction (timeout in 45 seconds)
Oct 07 10:25:21 xps-9550 avahi-daemon[716]: Joining mDNS multicast group on interface wlp2s0.IPv6 with address fe80::668:7f47:5a27:9830.
Oct 07 10:25:21 xps-9550 avahi-daemon[716]: New relevant interface wlp2s0.IPv6 for mDNS.
Oct 07 10:25:21 xps-9550 avahi-daemon[716]: Registering new address record for fe80::668:7f47:5a27:9830 on wlp2s0.*.
Oct 07 10:25:25 xps-9550 wpa_supplicant[754]: wlp2s0: CTRL-EVENT-REGDOM-CHANGE init=CORE type=WORLD
Oct 07 10:25:32 xps-9550 systemd[1]: NetworkManager-dispatcher.service: Succeeded.
Oct 07 10:26:06 xps-9550 NetworkManager[2739]: <warn>  [1633595166.7660] dhcp4 (wlp2s0): request timed out
Oct 07 10:26:06 xps-9550 NetworkManager[2739]: <info>  [1633595166.7661] dhcp4 (wlp2s0): state changed unknown -> timeout
Oct 07 10:26:06 xps-9550 NetworkManager[2739]: <info>  [1633595166.7662] device (wlp2s0): state change: ip-config -> failed (reason 'ip-config-unavailable', sys-iface-state: 'managed')

Changing WiFi encryption to 'Open' didn't help (as expected but had to try nevertheless).

I'm none the wiser but maybe a wiser man knows where to look further (WiFi driver or DSA switch driver?).

Edit/Addition: With kernel 5.15 I can't connect to either Home_Qu_L2_5G or Home_Qu_L2 also. On my mobile it is stuck at "Optaining IP address..."

You went to great lengths to reproduce the situation. Thanks for that. Even if there seems to be a problem, I'm glad to see that it wasn't a simple configuration mistake.

I’m keeping track of this issue and will work on it when I have time.

Sorry for the long delay. The bcm53xx target was moved over to DSA two days ago. I have just sent my patch adding support for Asus RT-AC88U. Can you try this image too whether you still have the issue?
Use openwrt-bcm53xx-generic-asus_rt-ac88u-squashfs.trx. It's compiled on the latest of master branch without the realtek DSA driver.

If you're still having issues, it shouldn't be related to my changes.

I tried it a couple of minutes ago. The behavior is still the same. Constantly trying to connect to the WLAN (you see the device on the status page as well as on the wireless page) but no connection can be established.

But this seems natural, because of the following behavior:

BusyBox v1.34.1 (2021-10-23 18:48:39 UTC) built-in shell (ash)

  _______                     ________        __
 |       |.-----.-----.-----.|  |  |  |.----.|  |_
 |   -   ||  _  |  -__|     ||  |  |  ||   _||   _|
 |_______||   __|_____|__|__||________||__|  |____|
          |__| W I R E L E S S   F R E E D O M
 -----------------------------------------------------
 OpenWrt SNAPSHOT, r17818-17b2c5531d29
 -----------------------------------------------------
root@AP_SQ:~# ping 192.168.5.1
PING 192.168.5.1 (192.168.5.1): 56 data bytes
64 bytes from 192.168.5.1: seq=0 ttl=64 time=0.822 ms
64 bytes from 192.168.5.1: seq=1 ttl=64 time=0.677 ms
64 bytes from 192.168.5.1: seq=2 ttl=64 time=0.720 ms
64 bytes from 192.168.5.1: seq=3 ttl=64 time=0.798 ms
^C
--- 192.168.5.1 ping statistics ---
6 packets transmitted, 6 packets received, 0% packet loss
round-trip min/avg/max = 0.650/0.719/0.822 ms
root@AP_SQ:~# ping 192.168.190.1
PING 192.168.190.1 (192.168.190.1): 56 data bytes
^C
--- 192.168.190.1 ping statistics ---
41 packets transmitted, 0 packets received, 100% packet loss
root@AP_SQ:~# 

Compare the results with 21.02.0 (kernel 5.4):

BusyBox v1.33.1 (2021-08-31 22:20:08 UTC) built-in shell (ash)

  _______                     ________        __
 |       |.-----.-----.-----.|  |  |  |.----.|  |_
 |   -   ||  _  |  -__|     ||  |  |  ||   _||   _|
 |_______||   __|_____|__|__||________||__|  |____|
          |__| W I R E L E S S   F R E E D O M
 -----------------------------------------------------
 OpenWrt 21.02.0, r16279-5cc0535800
 -----------------------------------------------------
root@AP_SQ:~# ping 192.168.5.1
PING 192.168.5.1 (192.168.5.1): 56 data bytes
64 bytes from 192.168.5.1: seq=0 ttl=64 time=0.935 ms
64 bytes from 192.168.5.1: seq=1 ttl=64 time=0.518 ms
64 bytes from 192.168.5.1: seq=2 ttl=64 time=0.741 ms
^C
--- 192.168.5.1 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.518/0.731/0.935 ms
root@AP_SQ:~# ping 192.168.190.1
PING 192.168.190.1 (192.168.190.1): 56 data bytes
64 bytes from 192.168.190.1: seq=0 ttl=64 time=0.685 ms
64 bytes from 192.168.190.1: seq=1 ttl=64 time=0.746 ms
64 bytes from 192.168.190.1: seq=2 ttl=64 time=0.572 ms
^C
--- 192.168.190.1 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.572/0.667/0.746 ms
root@AP_SQ:~#

With the snapshot tagging seems not possible, at least with the current configuration. E.g. when I change the untagged setting of port 1 (VLAN 1/VID 1) to tagged (of course I changed the setting on the switch as well), no connection to the router can be established on the tagged port.

OK, looks like this is a problem with kernel 5.10. I uploaded an image using the 5.4 kernel on the same release page. Can you give that a try?

I tried 5.4-openwrt-bcm53xx-generic-asus_rt-ac88u-squashfs.trx, but the router did not boot at all, even after flashing it again clean via CFE interface.

I just had the opportunity to try it on my router. As you have experienced, it won't boot properly. 5.4 is not used on master for bcm53xx anymore so I assume it's broken. I'm confident that this issue is not related to my changes as they're very minimal. I remember that you had this issue on 5.15 as well. This might be caused by the changes on the master branch, since there's no issue on OpenWrt 21.02.

Best thing you can do at this point is to open a bug report at https://bugs.openwrt.org/.

I have been quietly following this thread since I have an RT-AC88U that I want to install OpenWRT and run as my main router.

The RT-AC88U used to be my main router running Merlin, but the 5Ghz radio suddenly stopped working 2 years ago (and I retired it). Last month I dusted it off and I upgraded to a more recent factory firmware and the 5Ghz misteriously is live again. Now I am willing to give OpenWRT a try on it. However I understand from the latest posts that the current images in the @arinc9 git hub are not booting, is this correct?

EDIT: I just cloned @arinc9 github and did a build for the RT-AC88U. Build completed OK, however before trying these images I want to better understand the recovery process for this device since I do not want to brick it... :slight_smile:

No, it should work just fine. It's a bit outdated though, it'd be better for you to just compile your own image from the branch.

"bcm53xx: add support for Asus RT-AC88U" commit includes information to flash new firmware which also covers the case where the current firmware is broken.

As long as you don't mess with the et0macaddr nvram variable, you're good. Changing the value on this variable causes CFE to complain and fail to host the recovery webpage. I already included an initscript setting the correct value at every boot, so it's not a big deal even if you do mess with it.

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@scatman75 I've updated the 21.02 build to use 21.02.1. I recall that you have issues with kernel 5.10 so this should be useful for you.

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Thanks very much. I just installed the version. Works without problems with the existing configuration. So it really has to be the 5.10 kernel causing the problems. I opened a bug report https://bugs.openwrt.org/index.php?do=details&task_id=4112but I doubt the bug will be fixed as it only seems to apply to this type of Asus router.

Hopefully someone will figure it out by time.

We recently had wireless problems with Broadcom wireless on trunk which caused the system to hang. A commit fixing the issue is up, however even with that, my Wi-Fi SSIDs won't be advertised, meaning I can't see the wireless network from my phone.

Can you try the image called "test-openwrt-bcm53xx-generic-asus_rt-ac88u-squashfs.trx" and see if Wi-Fi works fine for you?

CC: @patient0

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Well the first result is that no wireless connection is made to phones or laptops.

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