apache/cassandra · warning

Cannot move the file

Error message

Cannot move the file {} to {} as the target file already exists.

What it means

During a recursive move, FileUtils.moveRecursively finds the target file already exists, so it refuses to copy over it and only logs a warning; the source file is left in place. The move silently skips that file.

Solutions

1. Remove or rename the pre-existing target file, then re-run the move
2. Ensure only one move operation targets a directory at a time
3. Clean up partially-completed prior moves before retrying
4. Verify data integrity after the move since the moved copy is skipped

Example fix

null

if (Files.exists(targetFile)) {
    // resolve conflict before moving
    Files.delete(targetFile); // or rename targetFile to a backup
}
FileUtils.moveRecursively(source, target);

boolean isTargetFree(Path target) { return !Files.exists(target); }

try {
    FileUtils.moveRecursively(source, target);
} catch (FileAlreadyExistsException | IOException e) {
    // resolve existing target, clean up, retry
}

When it happens

Trigger: Calling FileUtils.moveRecursively(source, target) (or a delegating move) where target directory already contains a file with the same relative name.

Common situations: Moving sstables into a directory that already holds a compaction or restore output; overlapping disk-move operations run concurrently; re-running an interrupted move script.

Understand the failure class

Background: "already exists" / EEXIST / FileAlreadyExistsException: what the 'file already exists' error means and how to fix it — this error's family across 37 libraries.

Related errors

• Cannot delete the directory
• Could not copy file to
• Could not perform startup sequence and join cluster
• ERR_WRONG_DISK_STATE
• ERR_WRONG_MACHINE_STATE

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/b1b77e636f18fcd0. Report an issue: GitHub.

Appendix: source

Thrown at src/java/org/apache/cassandra/io/util/FileUtils.java:710

        logger.info("Moving {} to {}" , source, target);

        if (Files.isDirectory(source))
        {
            Files.createDirectories(target);

            for (File f : new File(source).tryList())
            {
                String fileName = f.name();
                moveRecursively(source.resolve(fileName), target.resolve(fileName));
            }

            deleteDirectoryIfEmpty(source);
        }
        else
        {
            if (Files.exists(target))
            {
                logger.warn("Cannot move the file {} to {} as the target file already exists." , source, target);
            }
            else
            {
                Files.copy(source, target, StandardCopyOption.COPY_ATTRIBUTES);
                Files.delete(source);
            }
        }
    }

    /**
     * Deletes the specified directory if it is empty
     *
     * @param path the path to the directory
     */
    public static void deleteDirectoryIfEmpty(Path path) throws IOException
    {
        Preconditions.checkArgument(Files.isDirectory(path), String.format("%s is not a directory", path));

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