What exactly does 9001 socket exception [2] in mongodb error log mean?

  mongodb, question

Thu Dec 5 17:59:37.365 [conn1886970] SocketException handling request, closing client connection: 9001 socket exception [2] server []

Occasionally, this error will be reported. in this short period of 1~2 seconds, the program will not be able to connect with mongodb.

I have encountered this kind of situation, with the solution