apache/hadoop · error · InvalidBlockTokenException

Got access token error for connect ack, targets={}

Error message

Got access token error for connect ack, targets={}

What it means

Error "Got access token error for connect ack, targets={}" thrown in apache/hadoop.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java:3139

            false, false, null, storageId,
            targetStorageIds);

        // send data & checksum
        blockSender.sendBlock(out, unbufOut, throttler);

        // no response necessary
        LOG.info("{}, at {}: Transmitted {} (numBytes={}) to {}",
            getClass().getSimpleName(), DataNode.this.getDisplayName(),
            b, b.getNumBytes(), curTarget);

        // read ack
        if (isClient) {
          DNTransferAckProto closeAck = DNTransferAckProto.parseFrom(
              PBHelperClient.vintPrefixed(in));
          LOG.debug("{}: close-ack={}", getClass().getSimpleName(), closeAck);
          if (closeAck.getStatus() != Status.SUCCESS) {
            if (closeAck.getStatus() == Status.ERROR_ACCESS_TOKEN) {
              throw new InvalidBlockTokenException(
                  "Got access token error for connect ack, targets="
                   + Arrays.asList(targets));
            } else {
              throw new IOException("Bad connect ack, targets="
                  + Arrays.asList(targets) + " status=" + closeAck.getStatus());
            }
          }
        } else {
          metrics.incrBlocksReplicated();
        }
      } catch (IOException ie) {
        handleBadBlock(b, ie, false);
        LOG.warn("{}:Failed to transfer {} to {} got",
            bpReg, b, targets[0], ie);
      } catch (Throwable t) {
        LOG.error("Failed to transfer block {}", b, t);
      } finally {
        decrementXmitsInProgress();

View on GitHub (pinned to 2add963021)

Solutions

1. Ensure dfs.block.access.token.enable is enabled consistently across client, NameNode, and DataNode when security is on.
2. Check that the block access token presented by the client was issued by the NameNode for these targets and has not expired.

When it happens

Trigger: While establishing a data transfer connection (connect ack), the block access token validation fails for the given target DataNodes.

Common situations: Block access token validation failed while connecting to pipeline targets. Check token enablement consistency and clock skew between nodes.

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/5d7a67eb89e53cc1. Report an issue: GitHub.