apache/hadoop · error · AccessControlException

Router federation rename can't rename snapshot path. dst={}(

Error message

Router federation rename can't rename snapshot path. dst={}({})

What it means

Companion to the src check: RouterFederationRename.checkSnapshotPath also rejects a rename whose destination path addresses something inside a snapshot, i.e. the dst RemoteLocation destination contains '/.snapshot/'. Writing into a snapshot path is invalid in HDFS itself, and the fed rename pre-check surfaces it as an AccessControlException before any job is submitted.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/RouterFederationRename.java:198

        new Path("hdfs://" + srcLoc.getNameserviceId() + srcLoc.getDest());
    srcPath.getFileSystem(conf).access(srcPath.getParent(), FsAction.WRITE);
    // check dst path permission.
    Path dstPath =
        new Path("hdfs://" + dstLoc.getNameserviceId() + dstLoc.getDest());
    dstPath.getFileSystem(conf).access(dstPath.getParent(), FsAction.WRITE);
  }

  static void checkSnapshotPath(RemoteLocation src, RemoteLocation dst)
      throws AccessControlException {
    if (src.getDest()
        .contains(HdfsConstants.SEPARATOR_DOT_SNAPSHOT_DIR + Path.SEPARATOR)) {
      throw new AccessControlException(
          "Router federation rename can't rename snapshot path. src=" + src
              .getSrc() + "(" + src + ")");
    }
    if (dst.getDest()
        .contains(HdfsConstants.SEPARATOR_DOT_SNAPSHOT_DIR + Path.SEPARATOR)) {
      throw new AccessControlException(
          "Router federation rename can't rename snapshot path. dst=" + dst
              .getSrc() + "(" + dst + ")");
    }
  }

  /**
   * Build router federation rename job moving data from src to dst.
   * @param srcNs the source namespace id.
   * @param dstNs the dst namespace id.
   * @param src the source path.
   * @param dst the dst path.
   */
  private BalanceJob buildRouterRenameJob(String srcNs, String dstNs,
      String src, String dst) throws IOException {
    checkConfiguration(conf);
    Path srcPath = new Path("hdfs://" + srcNs + src);
    Path dstPath = new Path("hdfs://" + dstNs + dst);
    boolean forceCloseOpen =

View on GitHub (pinned to 2add963021)

Solutions

1. Target a live writable directory as the destination, never a path containing /.snapshot/
2. Validate dst before issuing the rename: reject any path with a /.snapshot/ component client-side
3. If the intent was restoring snapshot content, copy out of the snapshot with distcp to a regular destination instead

Example fix

# before
hdfs dfs -fs hdfs://router -mv /src /dstmount/.snapshot/snap1/restored
# after
hdfs dfs -fs hdfs://router -mv /src /dstmount/restored

// Validate the destination before rename
if (dst.contains(HdfsConstants.SEPARATOR_DOT_SNAPSHOT_DIR + Path.SEPARATOR)) {
  throw new IllegalArgumentException("Cannot rename into snapshot path: " + dst);
}

boolean isSnapshotPath(String path) {
  return path != null && path.contains("/.snapshot/");
}

try {
  dfs.rename(src, dst);
} catch (AccessControlException ace) {
  if (ace.getMessage() != null && ace.getMessage().contains("can't rename snapshot path. dst=")) {
    // choose a live writable directory as destination
  }
  throw ace;
}

When it happens

Trigger: rename(src, dst) across namespaces where the resolved dst contains /.snapshot/ - for example renaming onto /mount/.snapshot/snap1/newname or any target beneath a .snapshot directory.

Common situations: Scripts that construct destination paths from snapshot listings; mistaken cut-and-paste of a snapshot path as the rename target; tooling unaware that .snapshot is reserved.

Related errors

• Router federation rename can't rename snapshot path. src={}(
• Rename of {} to {} is not allowed, no eligible destination i
• Rename of {} to {} is not allowed. The remote location shoul
• Rename of {} to {} failed.
• Permission denied rename {}({}) to {}({}) Reason={}

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/2ceb0c17d35d09d9. Report an issue: GitHub.