Elsys device not rejoining after gateway offline (EU)

I had a situation where my lora gateway was offline for ~2 months and was brought back online.

I noticed the devices that were active on that gateway did not come back online (these are Elsys ERS motion sensors).

From viewing the uplinks coming from the back-online gateway I noticed that the devaddr of a device doing ConfirmedDataUp is the same as one in the device_activation table on chirpstack_ns postgres server. This leads me to think that the device is not configured to try to rejoin on not receiving downlinks.

  1. How do devices lose the Activation on the chirpstack application server? Is it based on time?
  2. Can I reinstate the existing activation and get the data flowing as expected?
  3. What else should I try?


gateway frames:

the app-server keeps a bunch of the shared-keys on redis, if redis is gone or the records expired, you are sort of out of luck, but i might be wrong.

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As far as I can tell, the app_s_key and the network session key are on postgres. I just don’t know how the server decides it is “unactivated” or not

@brocaar where is the device activation held specifically? Is it in redis or in the databases? What causes it to expire and can I reinstate it?