Examples of Hotcopy Errors

Hotcopy operations may fail in different ways but can be remedied by the user. Here, we list the most common errors and what they mean.

Caution: If there is a failure during execution of a hotcopy command then you must start a new hotcopy operation. You cannot resume the failed operation. A failure can possibly result in an unexpected termination of the SM, or a disk failure.

/hotcopyResults directory does not exist

Suppose that the /hotcopyResults directory does not exist. Execution of the hotcopy command with an archive destination of /hotcopyResults/test_archive would fail and you would see a message such as the following:

nuocmd hotcopy database --db-name db --default-backup-dir /hotCopyResults/test_archive --type full
'hotcopy database' failed: Failure while performing hot-copy: Error while sending engine request: Failed to create backup set /hotCopyResults/test_archive: No such file or directory

In the previous error message, notice that the name of the archive directory that could not be created is /hotcopyResults/test_archive.incomplete. During hotcopy execution, NuoDB adds the .incomplete extension to indicate that the hotcopy operation is in progress. The extension is removed when the hotcopy opeartion successfully completes. However, in the situation where the hotcopy operation fails, you might find instances of the .incomplete extension in your file system. It is up to you to remove any directories and files with a .incomplete extension. NuoDB does not store the location of .incomplete directories and files.

No storage manager could be found matching search criteria

If you attempt to run a hotcopy command without specifying a value for --default-backup-dir or a valid archive ID, the hotcopy operation fails in the following way:

nuocmd hotcopy database --db-name db --backup-dirs 42 /hotCopyResults/test_archive --type full
'hotcopy database' failed: Failure while performing hot-copy: No RUNNING SMs found for database dbName=db

Bad HotCopy Location

A hotcopy operation can fail because of a permission error. Below is an example:

nuocmd hotcopy database --db-name db --backup-dirs 1 /hotCopyArchives/test_archive --type full
'hotcopy database' failed: Failure while performing hot-copy: Error while sending engine request: Failed to create backup set temp directory /hotCopyArchives/test_archive/tmp/: Permission denied

Failure of SM during HotCopy

A hotcopy operation fails if the SM engine process fails for any reason. Below is an example:

nuocmd get hotcopy-status --coordinator-start-id 5 --hotcopy-id 5001619d-8f80-40fd-9e47-0bf7da1e02f0HotCopyResponse(begin_timestamp=2019-06-18 11:50:56, coordinator_start_id=5, end_timestamp=2019-06-18 11:51:08, id=5001619d-8f80-40fd-9e47-0bf7da1e02f0, message=Hot copy failed: Node 1 failed, status=failed)

Wrong database ID

A hotcopy operation fails if the SM engine process attempts to create a new backup on another database backup set directory. Below is an example:

nuocmd hotcopy database --db-name db4 --type incremental --backup-dirs 2 /hotCopyArchives/test_archive'hotcopy database' failed: Failure while performing hot-copy: Error while sending engine request: Destination backup set /hotCopyArchives/test_archive was created from a different archive

Trying to run Incremental Backup before invoking Full Backup

A hotcopy operation fails if an incremental backup is invoked before a full backup has been completed. Below is an example:

nuocmd hotcopy database --db-name db --backup-dirs 1 /hotCopyResults/test_archive --type incremental'hotcopy database' failed: Failure while performing hot-copy: Error while sending engine request: Cannot create incremental element. No full hot copy exists in backup set

Trying to run Journal Backup before invoking Full Backup

As with attempting incremental backup before full backup, a hotcopy operation fails if journal backup is invoked before a full backup has been completed. Below is an example:

nuocmd hotcopy database --db-name db --backup-dirs 1 /hotCopyResults/test_archive --type journal
'hotcopy database' failed: Failure while performing hot-copy: Error while sending engine request: Cannot create journal element. No full hot copy exists in backup set