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getnonce
Deprecated since version 4.0.
Client libraries use getnonce to generate a one-time password for authentication.
Applications should not invoke getnonce directly.
This command will be removed in a future release.
Starting in MongoDB 4.2, if the client that issued the getnonce disconnects before the operation completes, MongoDB marks the getnonce for termination (i.e. killOp on the operation).
killOp