apache/hadoop · error · HadoopIllegalArgumentException

Addition of user defined erasure coding policy is disabled.

Error message

Addition of user defined erasure coding policy is disabled.

What it means

Error "Addition of user defined erasure coding policy is disabled." thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/ErasureCodingPolicyManager.java:299

    return this.policiesByName.get(name);
  }

  /**
   * Clear and clean up.
   */
  public void clear() {
    // TODO: we should only clear policies loaded from NN metadata.
    // This is a placeholder for HDFS-7337.
  }

  /**
   * Add an erasure coding policy.
   * @return the added policy
   */
  public synchronized ErasureCodingPolicy addPolicy(
      ErasureCodingPolicy policy) {
    if (!userDefinedAllowed) {
      throw new HadoopIllegalArgumentException(
          "Addition of user defined erasure coding policy is disabled.");
    }

    if (!CodecUtil.hasCodec(policy.getCodecName())) {
      throw new HadoopIllegalArgumentException("Codec name "
          + policy.getCodecName() + " is not supported");
    }

    int blocksInGroup = policy.getNumDataUnits() + policy.getNumParityUnits();
    if (blocksInGroup > HdfsServerConstants.MAX_BLOCKS_IN_GROUP) {
      throw new HadoopIllegalArgumentException("Number of data and parity blocks in an EC group " +
          blocksInGroup + " should not exceed maximum " + HdfsServerConstants.MAX_BLOCKS_IN_GROUP);
    }

    if (policy.getCellSize() > maxCellSize) {
      throw new HadoopIllegalArgumentException("Cell size " +
          policy.getCellSize() + " should not exceed maximum " +
          maxCellSize + " bytes");

View on GitHub (pinned to 2add963021)

Solutions

1. Enable user-defined erasure coding policies by setting dfs.namenode.ec.userDefinedPolicy.enabled (or the equivalent config) to true, or use a built-in EC policy.

When it happens

Trigger: addErasureCodingPolicy when user-defined EC policies are disabled (dfs.namenode.ec.policies.user-defined disabled).

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/b580a20bb34ba850. Report an issue: GitHub.