Why does update_flash not reboot reliably with -R command line option?

I am using the update_flash linux utility for self-updating my Connect 9210 ME LX based devices.

Unfortunately, when used to update the rootfs partition, this utility does not reliably reboot the system (although started with the -R option). In about 1 out of 10 cases, after 100% successful and verified rootfs flashing, the system hangs instead of rebooting, and needs a manual reset.

This is highly unfortunate for my application where the 9210 ME LX based devices are not easily reachable for manual reset or power cycling.

I wonder what could be the reason for this. I would very much like to have a look at the source code for update_flash; is it available as open source?

how much RAM do you have free before transferring image onto module?
Also are you flashing modules one-by-one?
ie: it is recommended to transfer one image and update, delete file from RAM or whereever you have transfered , then transfer next one update…

Memory constraints can be a concern for update_flash utility

there’s enough RAM. The problem I see is not with the flashing process itself (which is fine, including CRC and verify), but the fact that the -R option does not reliably reboot the device after a successful flashing operation. Sometimes it works, sometimes it doesn’t.