apache/hadoop · error · SnapshotException

Failed to create snapshot: there are already {} snapshot(s)

Error message

Failed to create snapshot: there are already {} snapshot(s) and the {} snapshot limit is {}

What it means

Error "Failed to create snapshot: there are already {} snapshot(s) and the {} snapshot limit is {}" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/SnapshotManager.java:489

  }

  void checkFileSystemSnapshotLimit(int n) throws SnapshotException {
    checkSnapshotLimit(maxSnapshotFSLimit, n, "file system");
  }

  void checkPerDirectorySnapshotLimit(int n) throws SnapshotException {
    checkSnapshotLimit(maxSnapshotLimit, n, "per directory");
  }

  void checkSnapshotLimit(int limit, int snapshotCount, String type)
      throws SnapshotException {
    if (snapshotCount >= limit) {
      String msg = "there are already " + snapshotCount
          + " snapshot(s) and the "  + type + " snapshot limit is "
          + limit;
      if (isImageLoaded()) {
        // We have reached the maximum snapshot limit
        throw new SnapshotException(
            "Failed to create snapshot: " + msg);
      } else {
        // image is getting loaded. LOG an error msg and continue
        LOG.error(msg);
      }
    }
  }

  boolean isImageLoaded() {
    return fsdir.isImageLoaded();
  }
  /**
   * Delete a snapshot for a snapshottable directory
   * @param snapshotName Name of the snapshot to be deleted
   * @param now is the snapshot deletion time set by Time.now().
   * @param reclaimContext Used to collect information to reclaim blocks
   *                       and inodes
   */

View on GitHub (pinned to 2add963021)

Solutions

1. Delete unneeded snapshots or raise the per-directory snapshot limit (dfs.namenode.snapshot.max.allow.snapshots) if justified.

When it happens

Trigger: createSnapshot exceeds the configured snapshot count limit for the directory or system.

Common situations: Automated snapshot schedules accumulating snapshots until the limit is reached.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/add1af28f767f071. Report an issue: GitHub.