Just FYI if you are attempting to use Blink upgrade method (not clean install).
We run R80.30 T155 > R80.40 T91 and it failed:
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Investigation showed that CPUSE itself was to blame. Download agent repository was consuming over 20GB:
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And it had a lot of old stuff, looks like a background cleanup is not very efficient as we have been using CPUSE since R77.30. Lots of R77.30 and R80.10 bundes so I removed all those as well as R80.30 T111
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Additionally, /var/log/downloads had some older versions and just consumed space in /var/log, so removed those as well
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After that Blink upgrade succeeded with no issues.
Maybe something CPUSE / Blink team at R&D wants to add/consider - run a pre-check on repository and download directories and suggest cleanup?