Mongodb cannot start in fork mode, err number 100

  node.js, question

Due to the abnormal shutdown before, other services are normal after restart, but mongodb cannot be started with –fork.
My starting instructions are:
./mongod –dbpath=/root/dev/data/mongo_data/ –logpath=/root/dev/data/mongo_log/mongodb.log –fork –auth

The information returned is:

about to fork child process, waiting until server is ready for connections.
forked process: 5679
ERROR: child process failed, exited with error number 100

According to the Internet, the problem of deleting mongodb.lock and log files still exists.

I would like to add that the problem solved at that time was actually a very small white problem: the disk of that machine was full, because I had just contacted mongo at that time and suspected that my configuration was improper for a long time. finallydf -hIt will be clear in a moment.