[HDFS-4450] Duplicate data node on the name node after formatting data node

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.0.2-alpha
• Component/s: namenode
• Target Version/s: 2.0.2-alpha
• Assignee: Unassigned
• Reporter: WenJin Ma
• Created: 29/Jan/13 09:21
• Updated: 13/Aug/13 13:12

Description

Duplicate data node on the name node after formatting data node。
When we registered data node，use nodeReg.getXferPort() to find DatanodeDescriptor.

 DatanodeDescriptor nodeN = host2DatanodeMap.getDatanodeByXferAddr(
        nodeReg.getIpAddr(), nodeReg.getXferPort());

but add data node use node.getIpAddr().

    /** add node to the map 
   * return true if the node is added; false otherwise.
   */
  boolean add(DatanodeDescriptor node) {
    hostmapLock.writeLock().lock();
    try {
      if (node==null || contains(node)) {
        return false;
      }
      
      String ipAddr = node.getIpAddr();
      DatanodeDescriptor[] nodes = map.get(ipAddr);
      DatanodeDescriptor[] newNodes;
      if (nodes==null) {
        newNodes = new DatanodeDescriptor[1];
        newNodes[0]=node;
      } else { // rare case: more than one datanode on the host
        newNodes = new DatanodeDescriptor[nodes.length+1];
        System.arraycopy(nodes, 0, newNodes, 0, nodes.length);
        newNodes[nodes.length] = node;
      }
      map.put(ipAddr, newNodes);
      return true;
    } finally {
      hostmapLock.writeLock().unlock();
    }
  }