apache/hadoop · error · IllegalArgumentException

Unable to determine service address for namenode '{}'

Error message

Unable to determine service address for namenode '{}'

What it means

NNHAServiceTarget is the HAAdmin/ZKFC-side description of one NameNode. Its constructor resolves where that NameNode listens via DFSUtil.getNamenodeServiceAddr, which checks dfs.namenode.servicerpc-address.<ns>.<nn> and falls back to dfs.namenode.rpc-address.<ns>.<nn>. If both are absent, the address cannot be determined and an IllegalArgumentException naming the nnId is thrown — every later operation (failover, service state, health checks) needs this address.

Source

Thrown at hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/NNHAServiceTarget.java:76

  private String nsId;
  private boolean autoFailoverEnabled;

  /**
   * Create a NNHAServiceTarget for a namenode.
   * Look up addresses from configuration.
   *
   * @param conf          HDFS configuration.
   * @param nsId          nsId of this nn.
   * @param nnId          nnId of this nn.
   */
  public NNHAServiceTarget(Configuration conf,
      String nsId, String nnId) {
    initializeNnConfig(conf, nsId, nnId);

    String serviceAddr =
        DFSUtil.getNamenodeServiceAddr(targetConf, nsId, nnId);
    if (serviceAddr == null) {
      throw new IllegalArgumentException(
          "Unable to determine service address for namenode '" + nnId + "'");
    }

    this.addr = NetUtils.createSocketAddr(serviceAddr,
        HdfsClientConfigKeys.DFS_NAMENODE_RPC_PORT_DEFAULT);

    String lifelineAddrStr =
        DFSUtil.getNamenodeLifelineAddr(targetConf, nsId, nnId);
    this.lifelineAddr = (lifelineAddrStr != null) ?
        NetUtils.createSocketAddr(lifelineAddrStr) : null;

    initializeFailoverConfig();
  }

  /**
   * Create a NNHAServiceTarget for a namenode.
   * Addresses are provided so we don't need to lookup the config.
   *

View on GitHub (pinned to 2add963021)

Solutions

1. Add dfs.namenode.rpc-address.<ns>.<nn> (and optionally dfs.namenode.servicerpc-address.<ns>.<nn>) for every nn listed in dfs.ha.namenodes.<ns> on the machine running the tool, then retry.
2. Verify the ids you pass with -ns/-nn exactly match the configured dfs.ha.namenodes.<ns> entries (case and spelling).
3. Prefer distributing the NameNodes' full hdfs-site.xml to admin hosts instead of maintaining a hand-trimmed copy.

Example fix

<!-- before -->
<property><name>dfs.ha.namenodes.mycluster</name><value>nn1,nn2</value></property>
<!-- no dfs.namenode.rpc-address.* keys -> Unable to determine service address -->

<!-- after -->
<property><name>dfs.ha.namenodes.mycluster</name><value>nn1,nn2</value></property>
<property><name>dfs.namenode.rpc-address.mycluster.nn1</name><value>nn1-host:8020</value></property>
<property><name>dfs.namenode.rpc-address.mycluster.nn2</name><value>nn2-host:8020</value></property>

String svc = DFSUtil.getNamenodeServiceAddr(conf, nsId, nnId);
if (svc == null) {
  throw new IllegalStateException("Neither dfs.namenode.servicerpc-address."
      + nsId + "." + nnId + " nor dfs.namenode.rpc-address." + nsId + "." + nnId
      + " is set; refusing to build NNHAServiceTarget");
}
NNHAServiceTarget target = new NNHAServiceTarget(conf, nsId, nnId);

try {
  NNHAServiceTarget t = new NNHAServiceTarget(conf, nsId, nnId);
} catch (IllegalArgumentException e) {
  if (e.getMessage().contains("service address")) {
    throw new IllegalStateException("Missing dfs.namenode.rpc-address." + nsId
        + "." + nnId + " on this host; sync the full HA hdfs-site.xml", e);
  }
  throw e;
}

When it happens

Trigger: Constructing NNHAServiceTarget — directly or via 'hdfs haadmin' operations or ZKFC startup — on a node whose hdfs-site.xml lacks both address keys for the requested nsId/nnId pair; passing a -nn id that is not listed in dfs.ha.namenodes.<ns>; config loaded from a client-only directory without per-NN addresses.

Common situations: Admin host has a trimmed-down hdfs-site.xml with only dfs.nameservices and dfs.ha.namenodes but no per-NN rpc addresses; typo in the nn suffix (nn01 vs nn1) so the concatenated key matches nothing; config synced to gateway nodes missing the address block.

Related errors

• Unable to determine the name service ID.
• Configuration dfs.namenode.rpc-address must be suffixed with
• Unable to determine the name service ID. This is an HA confi
• No fencer configured for {}
• {} does not support method msync

AI-assisted analysis of apache/hadoop@2add963021 (2026-08-22). Data as JSON: /api/errors/a8ed7d48f81d5bfc. Report an issue: GitHub.