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Feature unavailable in Serverless Instances
Serverless instances don't support this feature at this time. To learn more, see Serverless Instance Limitations.
The oplog, a special capped collection, records operations that modify the data stored in your databases.
Add a User with Oplog Access
To access the oplog, a database user must have read access on
local database. To create a user with read access on
In the Security section of the left navigation, click Database Access.
Click the Database Users tab.
Click Add New Database User and enter a user name such as
Click Grant Specific Privileges and select the
readrole and the
localdatabase. This restricts the user to read operations on the
Enter a password and click Add User.
Access the Oplog
Connect to your cluster with the
mongosh, using the credentials of the new database user with access to the
Switch to the
> use local
The oplog collection is named
oplog.rs. Database write operations are recorded in date order, with a timestamp field and a wall clock field.
The timestamp field contains an integer with seconds since epoch.
To increase the size of an oplog for a cluster, see Set Oplog Size.
You cannot use the MongoDB command replSetResizeOplog to resize the oplog.