Error
Error Code:
242
MongoDB Error 242: Collection Creation Failure
Description
Error 242 indicates that MongoDB encountered an issue while attempting to create a new collection within a database. This prevents operations that rely on new collection creation, such as explicit `createCollection` commands or implicit collection creation during data insertion.
Error Message
Cannot Create Collection
Known Causes
3 known causesInsufficient User Permissions
The authenticated user lacks the necessary `createCollection` privilege for the target database or cluster.
Invalid Collection Name
The specified collection name violates MongoDB's naming conventions, such as containing forbidden characters or reserved prefixes.
Resource Constraints or System Issues
The MongoDB server or underlying system lacks sufficient resources (e.g., disk space, memory) or is experiencing other operational problems.
Solutions
4 solutions available1. Verify Database and Collection Name Validity easy
Ensure database and collection names adhere to MongoDB's naming conventions.
1
Check the database name for invalid characters. Database names cannot contain null characters ('\0').
No direct code needed for checking, but be mindful of names like 'my\0db'.2
Check the collection name for invalid characters. Collection names cannot contain null characters ('\0') or the '.' character.
No direct code needed for checking, but be mindful of names like 'my.collection' or 'coll\0name'.3
If you are using a driver, ensure that the string representation of your database and collection names is correctly escaped and does not violate these rules.
Example of invalid name in Python driver:
`db.client.get_database('my\0db').create_collection('my.collection')`
Corrected:
`db.client.get_database('mydatabase').create_collection('mycollection')`2. Check for Disk Space Issues medium
Confirm that the MongoDB data directory has sufficient free disk space.
1
Identify the MongoDB data directory. This is typically specified by the `dbpath` configuration option.
For `mongod` process:
`ps aux | grep mongod`
Look for the `--dbpath` argument or the `storage.dbPath` in config file.2
Check the available disk space on the partition where the data directory resides.
On Linux/macOS:
`df -h /path/to/your/mongodb/data/directory`
On Windows (PowerShell):
`Get-PSDrive -PSProvider FileSystem | Where-Object {$_.Root -eq 'C:\'}` (replace C:\ with your drive letter)3
If disk space is low, free up space by deleting unnecessary files or expanding the storage.
N/A3. Investigate MongoDB Server Logs medium
Examine MongoDB server logs for more detailed error messages.
1
Locate the MongoDB server log file. The location is usually specified by the `logpath` configuration option.
For `mongod` process:
`ps aux | grep mongod`
Look for the `--logpath` argument or the `systemLog.path` in config file.2
Open the log file and search for entries related to error code 242 or "Cannot Create Collection" around the time the error occurred.
On Linux/macOS:
`tail -f /path/to/your/mongodb.log | grep '242'`
On Windows (PowerShell):
`Get-Content C:\path\to\your\mongodb.log | Select-String -Pattern '242'`3
Analyze the surrounding log messages for clues about the root cause, such as permissions issues, file system errors, or specific configuration problems.
N/A4. Ensure Correct Permissions for MongoDB Data Directory medium
Verify that the MongoDB user has read/write permissions to its data directory.
1
Identify the user that the MongoDB server process is running as.
On Linux/macOS:
`ps aux | grep mongod`
Look at the first column of the `mongod` process line.2
Identify the MongoDB data directory (as found in Solution 2).
N/A3
Grant the MongoDB user read and write permissions to the data directory and its subdirectories.
On Linux/macOS (replace `mongodb_user` and `/path/to/mongodb/data`):
`sudo chown -R mongodb_user:mongodb_user /path/to/mongodb/data`
`sudo chmod -R u+rwX /path/to/mongodb/data`4
Restart the MongoDB service after changing permissions.
On Linux (systemd):
`sudo systemctl restart mongod`
On Windows (Services):
Open `services.msc`, find MongoDB, and restart.