apache/hadoop · error · IOException

Only read ${actualNumKeys} delegation keys out of ${expected

Error message

Only read ${actualNumKeys} delegation keys out of ${expectedNumKeys}

What it means

Error "Only read ${actualNumKeys} delegation keys out of ${expectedNumKeys}" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineImageViewer/OfflineImageReconstructor.java:966

        throw new IOException("SecretManager section had no " +
            "<numDelegationKeys>");
      }
      b.setNumKeys(expectedNumKeys);
      Integer expectedNumTokens =
          secretHeader.removeChildInt(SECRET_MANAGER_SECTION_NUM_TOKENS);
      if (expectedNumTokens == null) {
        throw new IOException("SecretManager section had no " +
            "<numTokens>");
      }
      b.setNumTokens(expectedNumTokens);
      secretHeader.verifyNoRemainingKeys("SecretManager");
      b.build().writeDelimitedTo(out);
      for (int actualNumKeys = 0; actualNumKeys < expectedNumKeys;
           actualNumKeys++) {
        try {
          expectTag(SECRET_MANAGER_SECTION_DELEGATION_KEY, false);
        } catch (IOException e) {
          throw new IOException("Only read " + actualNumKeys +
              " delegation keys out of " + expectedNumKeys, e);
        }
        SecretManagerSection.DelegationKey.Builder dbld =
            SecretManagerSection.DelegationKey.newBuilder();
        Node dkey = new Node();
        loadNodeChildren(dkey, "Delegation key fields");
        Integer id = dkey.removeChildInt(SECTION_ID);
        if (id == null) {
          throw new IOException("Delegation key stanza <delegationKey> " +
              "lacked an <id> field.");
        }
        dbld.setId(id);
        String expiry = dkey.removeChildStr(SECRET_MANAGER_SECTION_EXPIRY);
        if (expiry == null) {
          throw new IOException("Delegation key stanza <delegationKey> " +
              "lacked an <expiry> field.");
        }
        dbld.setExpiryDate(dateStrToLong(expiry));

View on GitHub (pinned to 2add963021)

Solutions

1. The XML is truncated or its <numDelegationKeys> count is wrong; correct the count or add the missing <delegationKey> stanzas.
2. Regenerate the fsimage XML with 'hdfs oiv' from a valid fsimage.

When it happens

Trigger: Thrown by oiv -r when the XML stream ends before all delegation keys declared by <numDelegationKeys> have been read, indicating a truncated or corrupt fsimage XML.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/dbef2428646089ae. Report an issue: GitHub.