apache/hadoop · error · NoECPolicySetException

No erasure coding policy explicitly set on {}

Error message

No erasure coding policy explicitly set on {}

What it means

NoECPolicySetException (org.apache.hadoop.hdfs.protocol.NoECPolicySetException, an IOException subclass) thrown by unsetErasureCodingPolicy when the directory has no raw.ec.policy xattr directly on itself. unsetPolicy removes only an explicit setting on that exact directory; a policy inherited from an ancestor is not 'explicitly set' and cannot be cleared from the child.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSDirErasureCodingOp.java:234

    FSDirectory fsd = fsn.getFSDirectory();
    final INodesInPath iip;
    List<XAttr> xAttrs;
    fsd.writeLock();
    try {
      iip = fsd.resolvePath(pc, src, DirOp.WRITE_LINK);
      // Write access is required to unset erasure coding policy
      if (fsd.isPermissionEnabled()) {
        fsd.checkPathAccess(pc, iip, FsAction.WRITE);
      }
      src = iip.getPath();
      xAttrs = removeErasureCodingPolicyXAttr(fsn, iip);
    } finally {
      fsd.writeUnlock();
    }
    if (xAttrs != null) {
      fsn.getEditLog().logRemoveXAttrs(src, xAttrs, logRetryCache);
    } else {
      throw new NoECPolicySetException(
          "No erasure coding policy explicitly set on " + src);
    }
    return fsd.getAuditFileInfo(iip);
  }

  /**
   * Add an erasure coding policy.
   *
   * @param fsn namespace
   * @param policy the new policy to be added into system
   * @param logRetryCache whether to record RPC ids in editlog for retry cache
   *                      rebuilding
   * @throws IOException
   */
  static ErasureCodingPolicy addErasureCodingPolicy(final FSNamesystem fsn,
      ErasureCodingPolicy policy, final boolean logRetryCache) {
    Preconditions.checkNotNull(policy);
    ErasureCodingPolicy retPolicy =

View on GitHub (pinned to 2add963021)

Solutions

1. Find where the policy is actually set: compare `hdfs ec -getPolicy` on the directory and each ancestor, then run `hdfs ec -unsetPolicy -path <that-directory>`.
2. In automation, catch NoECPolicySetException and treat unset as idempotent success.
3. Verify a direct policy exists with `hdfs dfs -getfattr -d /path` and look for the ec policy xattr (visible to authorized users).

Example fix

// before
dfs.unsetErasureCodingPolicy(new Path("/ec/child"));
// NoECPolicySetException: policy is inherited from /ec, not explicit on /ec/child

// after
dfs.unsetErasureCodingPolicy(new Path("/ec")); // unset at the dir where it was set

// Partial pre-check: a null *effective* policy (self or any ancestor) guarantees unset will throw.
if (dfs.getErasureCodingPolicy(p) == null) {
  // nothing set anywhere up the chain; skip unset (it would throw NoECPolicySetException)
}

import org.apache.hadoop.hdfs.protocol.NoECPolicySetException;

try {
  dfs.unsetErasureCodingPolicy(p);
} catch (NoECPolicySetException e) {
  // no explicit policy on this directory: inherited from an ancestor or never set.
  // Treat as success (idempotent unset) or walk up and unset at the real owner.
}

When it happens

Trigger: `hdfs ec -unsetPolicy -path /ec/child` where the policy was set on /ec; unsetting a directory that never had a direct policy; running unsetPolicy a second time; unsetting a directory whose policy xattr was already removed.

Common situations: Assuming unset on a descendant overrides inheritance (it does not - unset only works where set was used); idempotency-sensitive automation that reruns cleanup steps; ops runbooks that unset every level of a zoned tree.

Related errors

• Path not found: {}
• Policy '%s' does not match any enabled erasure coding polici
• The given erasure coding policy {} does not exist.
• Attempt to set an erasure coding policy for a file {}
• Cannot unset an erasure coding policy on a file {}

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/e0853035225de225. Report an issue: GitHub.