@nebulon If so, how do you recommend backing up the nodebb's MongoDB and files? and how to import data from old server?

when I was open the /admin/advanced/database, its shown below info:

NodeBB was unable to query the MongoDB database for relevant statistics. Please ensure that the user in use by NodeBB contains the "clusterMonitor" role for the "admin" database.

not authorized on <databaseName> to execute command { serverStatus: 1, lsid: { id: UUID("<UUID>") }, $clusterTime: { clusterTime: Timestamp(1600924060, 4), signature: { hash: BinData(0, <something>), keyId: <keyId> } }, $db: "<databaseName>" }

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