Thanks for pinpointing the exact change which causes the issues. Let's hope one of the developers can figure out what goes wrong and fix it.
Are you sure that MR42 works OK with a kernel 6.6 snapshot image? On my MR42, none of the WIFI radios was detected during booting when running such image. Can you please load the latest master snapshot for MR42 and attach the dmesg log? Thanks!
Sorry I have only flashed a snapshot to check for the mac address and I've not checked anything else. So there could be other issues due to changing to kernel 6.6
I had a spare MR52 and it was actually running a snapshot build from a while back (OpenWrt SNAPSHOT, r26340-9bdaebaff3, with kernel: Linux OpenWrt 6.6.30 #0 SMP Thu May 16 18:27:36 2024 armv7l GNU/Linux). It gets the MAC addresses right and I'm posting this via a Wifi connection through it, so Wifi is good enough for at least casual use.
I just upgraded a MR52 I'm using for real connectivity to 23.05.4 and it still gets the MAC addresses wrong (ie, boots with random MACs).
Comically when I installed OpenWRT on both of these, I must have switched the cases, because the MACs sticker on the 23.05.4 one matches the MAC addresses on the system running the SNAPSHOT build. 
So I just had a similar issue upgrading the MR52 from 23.05.4 to 23.05-SNAPSHOT.... no DNS/DHCP/.... but I could connect wirelessly if I gave myself a static IP address.
It turns out the ethernet interface match order changed between those two versions, so what was eth0 becase eth1 and vice-versa; you can imagine what kind-of mess that made. But the behavior looked very similar to yours from the external POV. Swapping the interfaces fixed everything besides the random MAC addresses -- that still requires main SNAPSHOT builds with a 6.6 kernel.
I just came back to this over the last couple of days. The latest 'stable' build 23.05.5 has exactly the same issues as does the snapshot build.
23.05.0 works as expected but has issues with the wifi drivers as documented.
Hope this gets fixed in later builds and this note helps someone else.
Cheers
Any difference with 23.05-SNAPSHOT?
https://mirror-03.infra.openwrt.org/releases/23.05-SNAPSHOT/targets/ipq806x/generic/
This is the snapshot I tested this morning.
Model
Cisco Meraki MR52
Platform
ipq806x/generic
Version
SNAPSHOT (r27889-7e542f6a77)
Again, if you swap your Ethernet interfaces, everything works just fine.. I have two of these running the 23.05-SNAPSHOT with 0 issues.
That is not possible as these devices are POE on eth0 we have 1 cable provision for them.
How are you swapping the ethernet interfaces. Can I somehow remap them in openwrt?
Cheers
I have it working with 23.05.5 by configuring a manual MAC on the eth0 interface that matches the sticker on the device. Then configuring the device bridge with both eth0 and eth1 physical interfaces with the same MAC as the eth0 interface. Only eth0 is plugged in but shows no activity on the port lights. All activity show on teh flashing lights on the eth1 interface that is not plugged in.
I am not sure how this is working like this but it is.
If there is a better way of 'swapping' the physical interfaces then let me know. As you know these devices can only be powered from eth0.
As of now 23.05.5 is working this way on this device with manual MAC addresses configured.
Cheers
[EDIT: I'm running 23.05-SNAPSHOT r24113-fa0a7e00e8... one of these was running the main snapshot but has since been pressed into service so I downgraded to the 23.05 branch...]
Oh, yeah, I forgot I needed to set the MAC address manually on all the interfaces. The LEDs are also reversed, but can be configured at your will.
I do feel like this was mentioned somewhere in the release notes, but yeah, it's a PITA when upgrading from earlier 23.05.X releases.
Sample interface declaration in /etc/config/network and /etc/config/wireless; I had to add macaddr definitions to all of the interfaces in both files:
config device
option name 'eth0'
option mtu '1500'
option ipv6 '0'
option macaddr '98:18:88:AA:BB:CC'
config wifi-iface 'wifinet4'
option device 'radio1'
option mode 'ap'
option ssid 'MySSID'
option encryption 'psk2'
option key '<redacted>'
option network 'lan'
option ifname 'phy1-lan0'
option macaddr '98:18:88:AA:BB:DD'
option ieee80211r '1'
option reassociation_deadline '20000'
option ft_over_ds '0'
option ft_psk_generate_local '1'
...and /etc/config/system:
config led 'led_eth0'
option name 'eth0 Activity'
option sysfs 'orange:lan2'
option trigger 'netdev'
option dev 'eth0'
list mode 'tx'
list mode 'rx'
config led 'led_eth1'
option name 'eth1 Activity'
option sysfs 'orange:lan1'
option trigger 'netdev'
option dev 'eth1'
list mode 'tx'
list mode 'rx'
config led
option name 'eth0 Link'
option sysfs 'green:lan2'
option trigger 'netdev'
option dev 'eth0'
list mode 'link'
config led
option name 'eth1 Link'
option sysfs 'green:lan1'
option trigger 'netdev'
option dev 'eth1'
list mode 'link'
Sorry for being so glib, but it is workable if a PITA to set up the first time.
@rkboni Many thanks for taking the time to respond. Yes, it is working as you say a PITA to config initially. Hopefully, these issues will be resolved in future builds.
Cheers
I've just installed a snapshot build OpenWrt SNAPSHOT / LuCI Master 24.291.55886~ade3606 on my spare MR52 and the mac issue has been fixed. So when OpenWrt 24 is released it should work as expected.
I have two PRs out for the MR52 to address a few things I've noticed:
- https://github.com/openwrt/openwrt/pull/16774 -- Fix for the random-MAC-address issues in 23.05.
- https://github.com/openwrt/openwrt/pull/16775 -- Fix for the network LEDs being reversed in 23.05.
@konus -- is #2 and issue in SNAPSHOT as well, or are the LEDs there correct and match the interfaces? (on 23.05, activity on LAN1 blinks the LAN2 led and vice-verse). If you can check that, I'll also address that in SNAPSHOT -- I don't have a spare router to check SNAPSHOT on as both of mine are being used for running the home Wifi ATM.
Cheers!
on the latest snapshot the network activity leds are still wrong. I've only got a poe cable plugged in but the led in the empty port is blinking.
I've not got a MR42 but that probably needs the same mac address fix since it uses the same eeprom to store the mac info as the mr52 and mr33
@konus thanks for confirming the LED issue!
Correct, MR42 will also have this issue, but since I don't have one to test I've been discouraged from applying the fix there.
I eBay'ed a few MR42's, so hopefully will have a fix for those as well in the next week or two.
Thanks to @robimarko the MR52 MAC address fix and LED swap have been merged into 23.05 branch, so the latest 23.05-SNAPSHOT builds should now have both issues addressed. The LED fix is also on main so latest SNAPSHOT builds should also have correct LED functioning on the MR52 (MAC addresses were not an issue there).
More on MR42 when I get my hardware and install OpenWRT on it. And @sparticle if you have a MR33 with OpenWRT already installed and want to test the same fix for a MR33, I can probably provide that as well.... but I'm not buying another older Meraki that has as high risk of becoming a doorstop as the MR33 
I'll also happily take a donation of a pre-installed MR33 if someone wants to send me one for "maintenance" purposes.