Adding OpenWrt support for Zyxel EX5601-T0

jekaho · June 21, 2025, 6:44pm

Does anyone here have two of these routers connected in WDS mode? I am experiencing a throughput issue, and it seems to be a known bug.

github.com/openwrt/openwrt

ZyXEL EX5601-T0/T-56 Very slow wireless speeds in repeater/sta mode: vht-msc goes from 7 to 0 under load

opened 11:32AM - 29 Jan 25 UTC

closed 08:10AM - 09 Mar 25 UTC

wirl

target/mediatek bug Official Image release/24.10

### Describe the bug Accidentally closed my [other issue](https://github.com/op…enwrt/openwrt/issues/17750) about this, but it is ok and took the opportunity to install the latest rc instead of my self compiled snapshot and re-test and re-open an issue about it. I would assume knowing exactly what imagine I run will help in fixing it unlike self compiled images. I am running this router in repeater/sta mode and getting very low speeds compared to my old routers. I don't know if it is related to the low tx power issue reported for this target too. The power doesn't seem to be an issue here., it's not stuck at a low value and changing it to a low value also didn't improve anything. What happens is that as soon as the connection is under load the speed drops to about 100mbit/s and stays there until the load is finished or cancelled. I have enabled/disabled things like hardware nat, setting packet steering to use all cores and irq balance. None of these improved or fixed the problem. The main thing I noticed is that the link stats change as soon as there is load on the connection, tx goes from vht-msc 7 to 0 and instantly goes back up once the load is stopped. I also noticed the tx link rate sits at 6mbit/s and the number of retries is very high. I did a lot of searching and found that many MediaTek chips suffer from similar/related issues. But nothing that really matches my issue. I am convinced that it is not user error. I have two other routers to test with and they're both fine and also run OpenWrt with pretty much the same settings. Speeds are as expected there. The issue must lie in the MediaTek driver somewhere. I really hope this issue can be solved. I bought this router to serve as repeater and to run a few containers on. Please let me know what logs I need to provide and what tests I can do. If this is a known issue that can't be fixed also please let me know. ### OpenWrt version r28417-daef29c75d ### OpenWrt release 24.10.0-rc7 ### OpenWrt target/subtarget mediatek/filogic ### Device Zyxel EX5601-T0 ubootmod ### Image kind Official downloaded image ### Steps to reproduce - Install snapshot and setup a client mode connection - Compare speeds to another router with the same client mode connection ### Actual behaviour Low speeds, maxing out around 100mbit/s ### Expected behaviour High speeds, minimally 600-700mbit/s ### Additional info _No response_ ### Diffconfig ```text ``` ### Terms - [x] I am reporting an issue for OpenWrt, not an unsupported fork.