Mongodb не запускается windows

Checking MongoDB Log Files

MongoDB log files are usually in the /var/log/mongodb or /var/log/mongo directory. These files have information about the database’s operations and errors.

Look for these error messages:

• «Unclean shutdown detected»
• «Old lock file»
• «Permission denied»
• «Couldn’t open file»

These messages often show the causes of service start failures. For example, «Unclean shutdown detected» means MongoDB didn’t shut down properly before.

tail -f /var/log/mongodb/mongod.log

Examining System Permissions

Correct file ownership and permissions are important for MongoDB to work. The database files and directories should belong to the MongoDB user and group.

To check permissions, use the ls -l command in the MongoDB data directory (often /var/lib/mongo). The output should show that the MongoDB user and group own the files.

Common permission issues include:

• Files owned by the root user instead of MongoDB
• Wrong read/write permissions on database files
• No execute permissions on directories

These problems can stop MongoDB from accessing files and directories, causing service start failures.

Repairing the MongoDB Database

To repair the MongoDB database, use the mongod command with the --repair option:

mongod --repair --dbpath /var/lib/mongo

This process may take time, based on your database size. Back up your data before starting, as repairing can cause data loss in rare cases.

The repair aims to fix data issues and remove corrupt data. After completion, you’ll see a message indicating a successful repair.

tail -f /var/log/mongodb/mongod.log

Correcting File Ownership and Permissions

Identify the correct owner for MongoDB files, usually the ‘mongod’ user and group. Change file ownership with the chown command:

sudo chown -R mongod:mongod /var/lib/mongo

This changes the owner and group of all files and directories in /var/lib/mongo to ‘mongod’.

Check the changes:

ls -l /var/lib/mongo

The output should show ‘mongod’ as the owner and group for all items.

Restarting the MongoDB Service

Restart MongoDB after applying fixes:

sudo systemctl restart mongod

Monitor the restart by checking the MongoDB log file:

tail -f /var/log/mongodb/mongod.log

Look for messages indicating a successful start, like «waiting for connections» or «MongoDB starting».

To confirm the service is running:

sudo systemctl status mongod

This should show the service as «active (running)».