apache/hadoop · error · IOException

No <snapshotCounter> entry found in SnapshotSection header

Error message

No <snapshotCounter> entry found in SnapshotSection header

What it means

Error "No <snapshotCounter> entry found in SnapshotSection header" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineImageViewer/OfflineImageReconstructor.java:1343

        bld.build().writeDelimitedTo(out);
      }
      recordSectionLength(SectionName.FILES_UNDERCONSTRUCTION.name());
    }
  }

  private class SnapshotSectionProcessor implements SectionProcessor {
    static final String NAME = "SnapshotSection";

    @Override
    public void process() throws IOException {
      FsImageProto.SnapshotSection.Builder bld =
          FsImageProto.SnapshotSection.newBuilder();
      Node header = new Node();
      loadNodeChildren(header, "SnapshotSection fields", "snapshot");
      Integer snapshotCounter = header.removeChildInt(
          SNAPSHOT_SECTION_SNAPSHOT_COUNTER);
      if (snapshotCounter == null) {
        throw new IOException("No <snapshotCounter> entry found in " +
            "SnapshotSection header");
      }
      bld.setSnapshotCounter(snapshotCounter);
      Integer expectedNumSnapshots = header.removeChildInt(
          SNAPSHOT_SECTION_NUM_SNAPSHOTS);
      if (expectedNumSnapshots == null) {
        throw new IOException("No <numSnapshots> entry found in " +
            "SnapshotSection header");
      }
      bld.setNumSnapshots(expectedNumSnapshots);
      while (true) {
        Node sd = header.removeChild(SNAPSHOT_SECTION_SNAPSHOT_TABLE_DIR);
        if (sd == null) {
          break;
        }
        Long dir;
        while ((dir = sd.removeChildLong(SNAPSHOT_SECTION_DIR)) != null) {
          // Add all snapshottable directories, one by one

View on GitHub (pinned to 2add963021)

Solutions

1. Add the missing <snapshotCounter> element to the SnapshotSection header of the fsimage XML.
2. Regenerate the fsimage XML with 'hdfs oiv' from a valid fsimage.

When it happens

Trigger: Thrown by oiv -r when the SnapshotSection header of the fsimage XML lacks the <snapshotCounter> element.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/9566e9d48ff49c47. Report an issue: GitHub.