EG25 DFOTA size constraints

Hello together,

currently I’m trying to update EG25-G modules in the field, connected to embedded devices running Linux.

The current fw version is EG25GGBR07A06M2G_01.001.01.001 received with AT+QMGR.

The FAE of our distributor provided some DFOTA zip files, but until now was not able to perform the update.

I tried updating from a FTP and HTTP server, but the DFOTA command failed with code 601 resp. 701.
Maybe this does not work if the modem is in use by the host system at the same time?

As an alternative, I wrote a small program to upload the .zip to the UFS partition and do a local DFOTA.
After uploading and issuing the DFOTA command only a single OK gets printed, but nothing else. Different AT commands still work.

Currently I suspect there might be a size issue with the DFOTA files:


The module has ~50MB free space on UFS. Now after upload only ~20MB are free. If I issue the DFOTA command the free space drops to 1-2KB.

Is it possible to receive intermediate DFOTA files that are smaller?

Serial output (DFOTA already uploaded and checksum checked):


+QFLDS: 20721664,50614272



+QFLDS: 8192,50614272


Best regards,
Thorsten Fuchs

Update over HTTP works reliably with the following steps:

  1. Stop ModemManager
  2. Reset modem (I use hw reset with the PERST pin, AT+CFUN=1,1 could also work)
  3. Wait for the modem to become available again
  4. Issue the AT+QFOTADL command

Local update by uploading the DFOTA file to UFS storage did not work. From the manual it seems like the modem tries to “download” the file from local storage to local storage again. At least this is my assumption. So if the file is bigger than 50% of free storage (~24MB on EG25-G) the update fails.