Mongodb failed to start: child process failed, exited with error number 100

the original link not directing a start: the child process failed, exited with the error number 100 (reference: refined into gold)

today when I was at the start the mongo, find don’t come, since an error: child process failed, exited with the error number 100 and then go to/var/log/mongo/mongod log view startup log, found:


Unclean shutdown detected.

Please visit for recovery instructions.


Sat Apr 20 09:40:31.286 [initandlisten] exception in initandlisten: 12596 old lock file, terminating

seems to be caused by not closing mongodb properly. Take a look at the link and launch it as a fix.

first delete the mongod. Lock under /var/lib/mongo

and then start in repair mode:

and then again at startup

you can now see that the mongod process exists and is working properly

then how to close mongodb normally?

can go to the official documents:

connect to the server through shell first:


use admin


or kill -15 < pid> , note that kill -9 can cause data file corruption

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