I have ReplicaSet and try to automate backup process.
There are secondary replica instance on host1:27017 and arbiter on host1:27018.
Process looks like:
1. stop mongod(host1:27017)
2. mongodump --dbpath /data/mongodb --out /tmp/backup --journal --directoryperdb
3. start mongod(host1:27017)
4. work with dump

If I run script from user shell It's work perfectly. But when I put It into cron, I don't receive any dumps and got "If you are running a mongod on the same path you should connect to that instead of direct data file access". All that time where was mongod.lock file in data directory.

Question is "why where are 2 different behavior in same environment?"