Have absolutly the same problem.
I was running 0.8.2 and after my vServer (Ubuntu 12.04) was down (hostsystem down) i had this effect.
I decided to rollback my vServer and everything was okay again for round about 18 hours. Then i got the same effect again without any downtime of the server.
I really though it has to do something with my system i don't understand.
So i just upgraded to 0.9.0, but after maybe 32 hours i now have the same problem again.
I Figured out that the \var\lib\redis\redis.rdb is messed up.
I made a rollback just couple hours ago, but somehow it seems my rdb is not in my server backup.
When i'm back home i can load a manually created backup file of my db and that should help.
Just a question of time when it will be messed up again.

I think i will have to completly cleanup the system from nodebb and all it's required packages and make a fresh install of 0.9.0

Since i'm not at home right now i can't provide any more informations.

just saw this https://community.nodebb.org/topic/6966/lost-all-my-data-help-please/2
two topics same problem

@Fez-Vrasta
hey there buddy,

first i have to thank you for that useful widget.
in your features list it says "show a message when the server is down"
well, i implemented the widget in the global sidebar.
But when our arma3 server is down or going to restart, the website is not able to load completly. it tries to reach the server which seem to be unreachable and does not jump into some kind of timeout.
since i am far away from beeing able to fix that, i would like to ask if you have any idea where i should take a look at.

thanks and regards,
larvell

Great theme!
Just finished the css editing to fit my requirements and having a more interesting view.
just one thing stoped working while switching to material theme.
I use the nodebb-plugin-editor-plus to give easy access to the known spoiler function. But somehow it does not show up as expandable spoiler. it just shows the full text. Any experience or suggestions on this?
You can view a capture of the spoiler at http://wot.searusu.eu/Unbenannt.JPG
If you are interested an anonymized screenshot of our website category list http://wot.searusu.eu/webseite.png

Regards,
Larvell