For the task https://sadservers.com/scenario/saint-john there is easy solution by usage of tool called lsof (short for list list open files) where man pages https://man7.org/linux/man-pages/man8/lsof.8.html gives details of usage. Take notice here: I use command kill -9, but in case of important tasks like email servers and similar where are data valuable please use kill -15

Solution in one picture:

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