apache/iceberg · error · RuntimeIOException

Namespace delete failed: %s

Error message

Namespace delete failed: %s

What it means

HadoopCatalog.dropNamespace deletes a namespace directory from the warehouse location. If the underlying FileSystem.delete call throws an IOException for any reason other than a non-empty namespace, it is wrapped in this RuntimeIOException carrying the namespace name. The delete is non-recursive, so a partially-populated directory will fail loudly rather than cascade.

Source

Thrown at core/src/main/java/org/apache/iceberg/hadoop/HadoopCatalog.java:350

    return Namespace.of(levels);
  }

  @Override
  public boolean dropNamespace(Namespace namespace) {
    Path nsPath = new Path(warehouseLocation, SLASH.join(namespace.levels()));

    if (!isNamespace(nsPath) || namespace.isEmpty()) {
      return false;
    }

    try {
      if (fs.listStatusIterator(nsPath).hasNext()) {
        throw new NamespaceNotEmptyException("Namespace %s is not empty.", namespace);
      }

      return fs.delete(nsPath, false /* recursive */);
    } catch (IOException e) {
      throw new RuntimeIOException(e, "Namespace delete failed: %s", namespace);
    }
  }

  @Override
  public boolean setProperties(Namespace namespace, Map<String, String> properties) {
    throw new UnsupportedOperationException(
        "Cannot set namespace properties " + namespace + " : setProperties is not supported");
  }

  @Override
  public boolean removeProperties(Namespace namespace, Set<String> properties) {
    throw new UnsupportedOperationException(
        "Cannot remove properties " + namespace + " : removeProperties is not supported");
  }

  @Override
  public Map<String, String> loadNamespaceMetadata(Namespace namespace) {
    Path nsPath = new Path(warehouseLocation, SLASH.join(namespace.levels()));

View on GitHub (pinned to 86d9c8fc54)

Solutions

1. Check the cause exception (getCause()) to see the underlying FileSystem error and fix it (permissions, cluster availability, safe mode).
2. Re-check whether the namespace still exists before retrying; a concurrent delete may have already removed it.
3. Verify the caller has write/delete permission on the namespace directory and its parent.
4. Retry after the HDFS cluster / object store is healthy, since empty directories can also trip the NamespaceNotEmptyException path.
5. If namespaces frequently race with other writers, serialize namespace administration operations externally.

Example fix

// before
catalog.dropNamespace(Namespace.of("reports"));
// after
try {
  catalog.dropNamespace(Namespace.of("reports"));
} catch (RuntimeIOException e) {
  LOG.warn("Namespace delete failed for reports: {}", e.getCause());
  // inspect cause: permissions, safe mode, concurrent delete
}

Namespace ns = Namespace.of("db");
Map<String,String> meta = catalog.loadNamespaceMetadata(ns); // throws NoSuchNamespaceException if missing
// confirm emptiness implicitly: dropNamespace throws NamespaceNotEmptyException if tables exist

boolean canDrop = catalog.namespaceExists(ns) && catalog.loadNamespaceMetadata(ns) != null;

try {
  catalog.dropNamespace(ns);
} catch (NamespaceNotEmptyException e) {
  // drop tables first
} catch (RuntimeIOException e) {
  Throwable cause = e.getCause(); // decide: permissions / concurrency / availability
}

When it happens

Trigger: Calling catalog.dropNamespace(Namespace) when fs.delete(nsPath, false) throws IOException — e.g. permission denied, the path was concurrently removed by another process, HDFS name-node unavailable, or a stale file handle.

Common situations: Distributed clusters where another job deletes the namespace path between the emptiness check and the delete; HDFS Safe Mode leaving the namespace in read-only state; misconfigured fs permissions on the warehouse location; network partitions to HDFS/S3.

Related errors

• Failed to list tables under: %s
• Failed to delete file: %s
• Failed to list namespace under: %s
• Failed to delete file: %s
• Failed to get status for file: %s

AI-assisted analysis of apache/iceberg@86d9c8fc54 (2026-09-12). Data as JSON: /api/errors/1564eb3acba32b07. Report an issue: GitHub.