manual upgrade to 5.0 & OVERLEAF fails

[Pfiffikus]

Running bin/up ends up in Initiating Mongo replica set... time="2024-05-21T09:44:01+02:00" level=warning msg="The "SHARELATEX_DATA_PATH" variable is not set. Defaulting to a blank string." invalid spec: :/var/lib/sharelatex: empty section between colons

Specifying SHARELATEX_DATA_PATH results in Initiating Mongo replica set... Rebranding from ShareLaTeX to Overleaf The Toolkit has adopted to Overleaf brand for its variables. Your config/overleaf.rc still has 1 variables using the previous ShareLaTeX brand. Moving forward the 'SHARELATEX_' prefixed variables must be renamed to 'OVERLEAF_'. You can migrate your config/overleaf.rc to use the Overleaf brand by running: toolkit$ bin/rename-rc-vars

How to escape this dilemma? Where to find a step-by-step description, what to do instead of an interrupted bin/upgrade?