Live Migration Troubleshooting¶
Before the Live Migration process begins, Atlas performs a validation check to ensure that all the necessary form fields and parameters are functional and correct. If any parameters are invalid, Atlas returns an error and Live Migration does not proceed.
Listed below are some common Live Migration validation errors and suggestions for what to check if you encounter them.
Common Live Migration Validation Errors¶
Could not reach specified source
Could not resolve hostname
No IP address was found for the given hostname. Confirm that the given hostname is correct and publicly accessible.
Invalid SSL options provided
If you are using SSL:
If you are not using SSL:
The username or password is not correct
User not authorized to execute command
In order to perform the Live Migration procedure, the MongoDB user must have sufficient system privileges. See Source Cluster Security for details.
Source disk usage is too large for destination
Different Atlas service tiers have different amounts of disk space available. Ensure that your Atlas cluster has enough disk space for all the data on your source cluster. See Create a New Cluster for details on cluster sizing.
Source appears to be a standalone
Your source deployment must be a MongoDB replica set. If your source deployment is currently a standalone node, convert it to a single-node replica set before performing Live Migration.
Unable to process the provided CA file
Confirm that your CA file is complete and correctly pasted into the Live Migration modal window.
Common Post-Validation Errors¶
Could not retrieve the latest oplog entry from the source: not found
Could not determine if --host is a replica set: error connecting to db server: no reachable servers
Error applying oplog entries during initial sync: renameCollection command encountered during initial sync. Please restart mongomirror.
Renaming a collection on the source cluster during Live migration may trigger this error.
Unsupported index error
Certain types and configurations of indexes which were allowable in earlier versions of MongoDB are no longer supported in more recent versions. Check the release notes for the MongoDB version on your destination cluster for possible conflicts. If necessary, drop any indexes which cause errors and rebuild them after migration is complete.
Error while tailing the oplog on the source: Checkpoint not available in oplog
Live Migrate uses the source oplog to sync operations which occur on the source cluster during the Live Migration procedure. If the source cluster oplog size is too small, it might not be able to record all the operations that occur on the source cluster during the sync, and Live Migrate falls too far behind to catch up.
If you see this error, check the size of the source cluster oplog using the rs.printReplicationInfo() command. You can increase the size of the source oplog to support a replication window that is long enough to complete the Live Migration procedure.