apache/hadoop · error · IllegalArgumentException

Too many arguments.

Error message

Too many arguments.

What it means

CreateSnapshot.processOptions (SnapshotCommands.java:70) throws IllegalArgumentException('Too many arguments.') when more than two positional arguments remain after option parsing. createSnapshot accepts exactly one required directory plus at most one optional snapshot name; anything beyond that is rejected before the last argument is popped as the name.

Source

Thrown at hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/shell/SnapshotCommands.java:70

    public static final String USAGE = "<snapshotDir> [<snapshotName>]";
    public static final String DESCRIPTION = "Create a snapshot on a directory";

    private String snapshotName = null;

    @Override
    protected void processPath(PathData item) throws IOException {
      if (!item.stat.isDirectory()) {
        throw new PathIsNotDirectoryException(item.toString());
      }
    }
    
    @Override
    protected void processOptions(LinkedList<String> args) throws IOException {
      if (args.size() == 0) {
        throw new IllegalArgumentException("<snapshotDir> is missing.");
      } 
      if (args.size() > 2) {
        throw new IllegalArgumentException("Too many arguments.");
      }
      if (args.size() == 2) {
        snapshotName = args.removeLast();
      }
    }

    @Override
    protected void processArguments(LinkedList<PathData> items)
    throws IOException {
      super.processArguments(items);
      if (numErrors != 0) { // check for error collecting paths
        return;
      }
      assert(items.size() == 1);
      PathData sroot = items.getFirst();
      Path snapshotPath = sroot.fs.createSnapshot(sroot.path, snapshotName);
      out.println("Created snapshot " + snapshotPath);
    }    

View on GitHub (pinned to 2add963021)

Solutions

1. Pass at most two arguments: directory and optional name: 'hadoop fs -createSnapshot /data mysnap'
2. Quote variables in scripts ('"$SNAPDIR"') and validate they contain a single path
3. Create snapshots per directory with separate invocations instead of batching directories in one command

Example fix

# before
hadoop fs -createSnapshot /data /backup mysnap
# createSnapshot: Too many arguments.

# after
hadoop fs -createSnapshot /data mysnap
hadoop fs -createSnapshot /backup mysnap

# exactly 1 or 2 args
if (( $# < 1 || $# > 2 )); then echo "usage: createSnapshot <dir> [name]"; exit 2; fi
hadoop fs -createSnapshot "$@"

catch (IllegalArgumentException e) when 'Too many arguments' -> drop extras; keep exactly <snapshotDir> [<snapshotName>] and re-run one command per directory

When it happens

Trigger: 'hadoop fs -createSnapshot /dir name extra', 'hadoop fs -createSnapshot /dir /otherdir name' — three or more non-flag tokens. Typically caused by an unquoted variable expanding to multiple words (SNAPDIR='/data /data2').

Common situations: Shell scripts passing unquoted or multi-word variables; commands assembled by string concatenation that accidentally append another path; operators assuming multi-directory or name+comment arguments are supported like in other snapshot subcommands (renameSnapshot takes three).

Related errors

• <snapshotDir> is missing.
• Invalid read parameters: buf.length=%d, off=%d, len=%d
• Move destination must be different from source for %s.
• offset: %s is out of range [%s, %s]
• Invalid start or len parameter

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/f875101ae8a5df49. Report an issue: GitHub.