I tried flashing the SD cards with older versions of the worker image (e.g., 25.5.22 to 25.6.25). However, none of the flashed SD cards gave blue-light on the HAT nor did they get recognized by the watchdog. I have been troubleshooting this issue for 3 days now, and just realized that this does not happen with version 25.7.2 (most recent version - 24.07.2025).
I tested many things, but using the 24.07.2025 version was the only trial that gave positive results. Has anyone else experienced this?
Hi @sharknaro,
Yes there was a problem in those worker images (fresh installs) that was fixed in 25.7.2. If you need those versions, 25.5.22 to 25.6.25, you may need to install a previous version, and perform an upgrade(s) to get to the version you need.
Cameron
Thank you for the hint! However, the workers are still not getting recognized by the watchdog, even after flushing with the most recent software version and having constant blue light on the HAT. Could this still be caused by an existing problem?
Hm, thats odd then. It’s possible your network has turned off “mdns”, which is the communication protocol the watchdog uses. Turning off mdns is common in large networks. Are you able to find the workers via your local computer? If you remove the worker’s SD card (after powering off), place it into a computer again, look for the bootfs dir, and find a network_info.txt file there - is there an IP address assigned to the Pioreactor (should be near the top).
Would this happen randomly? The network has not been changed from the intial time it was setup. We just flashed the SD cards and could not add them back to the network.
No IP address is assigned. But it makes sense, assuming that the IP is set after the worker is added to the cluster, right?
The IP address is assigned when the Pi connects to the network, independent of being part of a cluster.
So if there is no IP address, it’s not connecting to the network. If you’re using a local-access-point, confirm that the wifi details are all correct and you’re not adding too many Pioreactors (~8 is max). If it’s your institution’s network, is this being connected over ethernet or wifi?
Yes, we are using local access point (LAP). We have changed the firmware through sudo update-alternatives --config cyfmac43455-sdio.bin as suggested. We had 12 pioreactors in the LAP. After flashing, I removed the worker(s) from the LAP, so there should be available space for them to be added.
The LAB SSID and password details must be correct because I have entered them multiple times. In addition, I also tried to add the worker to a fresh LAP with no workers. However, the same issue, the worker did not get recognized.
It shows constant blue light as described in the The blue LED is constantly on?.
The link suggests hardware issue or missing config.ini. It cannot be hardware error because the HAT behaves perfectly fine with other SD cards that is already in the cluster, and the config.ini is missing because the worker is not added to the cluster yet. I have tested all this with 25.5.22. Maybe this is why I am not being able to add to the cluster - because the leader is 25.5.22? I can try to make clean flash of leader and worker with the most recent software version.