You shouldn't change anything in Redis itself, you must use the Zentyal GUI. If for some reason you need it, you could use the script '/usr/share/zentyal/clean-conf network that resets the module from scratch. I am not sure if there would be an issue due to the module dependencies. So, if you try it, make sure you did a backup of the server.
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“This world is ours, and by the Holy Light we will keep it safe, now and forever".