@JohnGuan If you want to backup NodeBB's mongodb, then go to the app's backup -> create backup. In the backup, there will be a mongodbdump file. As for importing, please see https://docs.cloudron.io/guides/import-mongodb/

@robw @alex-adestech An update on this. Crux of the issue is that the indices name generated are too long. @alex-adestech pointed out to me that this issue only sorted out in MongoDB 4.4 and not even MongoDB 4.2. Searching through the rocket.chat issue tracker I saw only person hit this and nobody replied. Search further, I found that Rocket.Chat doesn't even support MongoDB 4.2. The releases page mentions the versions they test with - https://github.com/RocketChat/Rocket.Chat/releases. This got me wondering why we hit this issue. Well, the answer it turns out is that Cloudron generates 32 byte mongodb database names for apps. This in turn ends up affecting the length of the index. I have made a fix now for Cloudron 5.6 that generates shorter names. (We have had to do something similar for apps using MySQL as well in the past).

@girish Ah yes, sorry. Should've looked. At least maybe this will direct someone to the docs if they end up here again.

Currently there is no supported way to connect to the MongoDB addon instance from the outside. Apps can only access it via the local network on the server itself. Can you describe you use-case a bit, so we can see if we should add such support? Thanks.