{"record":{"id":"449be21e33937929","repo":"apache/hadoop","slug":"invalid-entry-fault-tolerance-requires-multiple-d","errorCode":null,"errorMessage":"Invalid entry, fault tolerance requires multiple destinations {}","messagePattern":"Invalid entry, fault tolerance requires multiple destinations (.+?)","errorType":"validation","errorClass":"IllegalArgumentException","httpStatus":null,"severity":"error","filePath":"hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/store/records/MountTable.java","lineNumber":411,"sourceCode":"    }\n    for (RemoteLocation loc : getDestinations()) {\n      String nsId = loc.getNameserviceId();\n      if (nsId == null || nsId.length() == 0) {\n        throw new IllegalArgumentException(\n            ERROR_MSG_INVALID_DEST_NS + this);\n      }\n      if (loc.getDest() == null || loc.getDest().length() == 0) {\n        throw new IllegalArgumentException(\n            ERROR_MSG_INVALID_DEST_PATH + this);\n      }\n      if (!loc.getDest().startsWith(\"/\")) {\n        throw new IllegalArgumentException(\n            ERROR_MSG_ALL_DEST_MUST_START_WITH_BACK_SLASH + this);\n      }\n    }\n    if (isFaultTolerant()) {\n      if (getDestinations().size() < 2) {\n        throw new IllegalArgumentException(\n            ERROR_MSG_FAULT_TOLERANT_MULTI_DEST + this);\n      }\n      if (!isAll()) {\n        throw new IllegalArgumentException(\n            ERROR_MSG_FAULT_TOLERANT_ALL + this);\n      }\n    }\n  }\n\n  @Override\n  public long getExpirationMs() {\n    return 0;\n  }\n\n  @Override\n  public int hashCode() {\n    return new HashCodeBuilder(17, 31)\n        .append(this.getSourcePath())","sourceCodeStart":393,"sourceCodeEnd":429,"githubUrl":"https://github.com/apache/hadoop/blob/2add9630210752f88ceb1bb74eb65e37bf41da8e/hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/store/records/MountTable.java#L393-L429","documentation":"Error \"Invalid entry, fault tolerance requires multiple destinations {}\" thrown in apache/hadoop.","triggerScenarios":"MountTable validation: fault-tolerant mode requested but fewer than two destinations configured.","commonSituations":"Admin enabled fault tolerance on a mount with only one destination.","solutions":["Add at least two destination nameservices when enabling fault tolerance on the mount entry.","Or remove the fault-tolerance flag if a single destination is intended."],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"2add9630210752f88ceb1bb74eb65e37bf41da8e","analyzedAt":"2026-08-22T19:55:07.957Z","schemaVersion":2},"datasetVersion":"2026-08-22T20:17:22.307Z"}