namenode and datanode in hadoop

[[-Z $ java_home]; then 4. Add configuration items in the hadoop configuration file: (The configuration file is configured directly in the hadoop-cdh4b1/etc/hadoop directory), I used a total of five machines here: 10.250.8.106 namenode 10.250.8.107 namenode 10.250.8.108

Datanode (simple method)Dna_register:datanode Re-registration (simple method)dna_finalize: Submit Upgrade (Simple method)dna_recoverblock: Recovering data blockscopying data blocks to other Datanode is performed by the Transferblocks method. Note that the returned command can contain more than one block of data, each of which can contain multipleDestination address. The Transferblocks method initiates a Da

In general, the correct approach is to prioritize the configuration file and then start/stop the corresponding process on the specific machine. Some of the information on the web said that in the adjustment of the configuration file, the first use of host name instead of IP configuration. In general, the method of adding/removing Datanode and Tasktracker is very similar, except that there are slight differences between the operation's configuration it

Tags:-name pool views POS full stat Find storage heightThe Datanode process is missing a description of the problemThe recent configuration of Hadoop has been followed by the use of the JPS command after startup:Can't see the Datanode process, but can work normally, isn't it amazing?After a Baidu Google, came to the conclusion:Before and after I started

Questions Guide:1. How do I start looking at problems when Hadoop is having problems?2, Datanode can not start, how should we solve?3. How to add Datanode or Tasktracker dynamically?First, the problem descriptionWhen I format the file system many times, such as[Email protected]:/usr/local/hadoop-1.0. 2# Bin/

HDFs is initiated by a $hadoop_home/bin/start-dfs.sh (or start-all.sh) script on the Namenode machine. The script starts the Namenode process on the machine running the script, and the Datanode process is started on the slaves machine, and the list of slave machines is saved in the Conf/slaves file, one machine at a time. And a SNN process is started on another

The storage path in the datanode node stores different file data blocks. HDFS's implementation of the node storage path is abstracted into a storagedirectory class. Storagedirectory File The storagedirectory class contains three attributes: File root;// A local path configured in DFS. Data. dirFilelockLock;// Exclusive lock, synchronous control node operation on the storage directory in_use.lockStoragedirtype dirtype;//

namenode machine. This script starts the namenode process on the machine that runs the script, and the datanode process is started on the server Load balancer instance. The list of Server Load balancer instances is saved in the conf/Server Load balancer file, with one machine in one row. An SNN process will be started on another machine, which is specified by th

Hadoop executes commands multiple times: After Hadoop Namenode-format, after discovering that Hadoop was started again, the Datanode node did not start properly, and the error code was as follows: Could only being replicated to 0 nodes, instead of 1, there are many reasons

In general, the correct approach is to prefer the configuration file and then start the detailed machine corresponding to the process/stop operation.Some of the information on the web said that in the adjustment of the configuration file, the first use of host name instead of IP configuration.In general, the method of adding/removing Datanode and Tasktracker is very similar, only a small difference between the operation's configuration items and the c

resulting namenode (standby) hangs, the developer adjusts the frequency of the MapReduce job run. In order to simulate the long-running status as soon as possible, pumping a 1-day run once the job changed to 5 minutes to run once. After running the 2-day job, see the Namenode host's historical memory usage trend graph from the Cloud Platform CAs Monitor as follows Number 22nd 17:00~18:00 increased the

Hadoop datanode node time-out settingDatanode process death or network failure caused datanode not to communicate with Namenode,Namenode will not immediately determine the node as death, after a period of time, this period is temporarily known as the timeout length.The defau

Problem Description The department's Hadoop cluster has been running for one months and today needs to be tweaked, but it suddenly turns out that Hadoop is not shutting down properly. Hadoop version: 2.6.0 The details are as follows: [Root@master ~]# stop-dfs.sh stopping namenodes on [master] Master:no namenode to sto

This article is partially transferred from Hadoop 2.0 NameNode HA and Federation practicesThis article is part of a tutorial on automatic ha+federation+yarn configuration in detail hadoop2 A Hadoop 20 HA implementation 1 uses shared storage to synchronize the edits information between two NN 2 Datanode hereinafter refe

JPS no Namenode after Hadoop startedGenerally due to two or more than two times the format of the Namenode, there are two ways to solve:1. Delete all data from Datanode2. Modify the Namespaceid of each datanode (located in the/home/hdfs/data/current/version file) or modify the Namespaceid of

Scenario: Centos 6.4 X64 Hadoop 0.20.205 Configuration file Hdfs-site.xml When creating the data directory used by the Dfs.data.dir, it is created directly with the Hadoop user, Mkidr-p/usr/local/hdoop/hdfs/data The Namenode node can then be started when it is formatted and started. When executing JPS on the Datanode