hadoop2

问题 I'm getting below issue while accessing ApplicationMaster UI from the RM WebUI (hadoop 2.6.0). There is no standalone WebProxy server running. The Proxy is running as a part of ResourceManager. "HTTP ERROR 500 Problem accessing /proxy/application_1431357703844_0004/. Reason: Connection refused" Log entries in resourcemanager logs: 2015-05-11 19:25:01,837 INFO webproxy.WebAppProxyServlet (WebAppProxyServlet.java:doGet(330)) - ubuntu is accessing unchecked http://slave1:51704/ which is the app

问题 I'm getting below issue while accessing ApplicationMaster UI from the RM WebUI (hadoop 2.6.0). There is no standalone WebProxy server running. The Proxy is running as a part of ResourceManager. "HTTP ERROR 500 Problem accessing /proxy/application_1431357703844_0004/. Reason: Connection refused" Log entries in resourcemanager logs: 2015-05-11 19:25:01,837 INFO webproxy.WebAppProxyServlet (WebAppProxyServlet.java:doGet(330)) - ubuntu is accessing unchecked http://slave1:51704/ which is the app

问题 Because HBase is based on HDFS, and that HDFS doesn't have update features, I was wondering if the update operations on it rewrites the whole HFILE files on hadoop? thanks 回答1: There are no updates in HBase. When you perform a delete in HBase (the whole row or particular cells), a special deletion marker is added to a cell. Upcoming scans or get operations would not see that cell(s). When you perform an insert, you just create a new cell with current timestamp. Scan and get operations will

问题 I am following this video tutorial trying to set up hadoop on my machine. How to Install Hadoop on Windows 10 I've setup it successfuly: no errors while executing start-all.xml from sbin directory. But when I am trying to execute my WordCount.jar file there is an error ocurred: 2/23 11:42:59 INFO localizer.ResourceLocalizationService: Created localizer for container_1550911199370_0001_02_000001 19/02/23 11:42:59 INFO localizer.ResourceLocalizationService: Localizer failed org.apache.hadoop

问题 I was learning hadoop, I found number of reducers very confusing : 1) Number of reducers is same as number of partitions. 2) Number of reducers is 0.95 or 1.75 multiplied by (no. of nodes) * (no. of maximum containers per node). 3) Number of reducers is set by mapred.reduce.tasks . 4) Number of reducers is closest to: A multiple of the block size * A task time between 5 and 15 minutes * Creates the fewest files possible. I am very confused, Do we explicitly set number of reducers or it is

问题 Hi guys I've been learning about Amazon EMR lately, and according to my knowledge the EMR cluster lets us choose 3 nodes. Master which runs the Primary Hadoop daemons like NameNode,Job Tracker and Resource manager. Core which runs Datanode and Tasktracker daemons. Task which only runs TaskTracker only. My question to you guys in why does EMR provide task nodes? Where as hadoop suggests that we should have Datanode daemon and Tasktracker daemon on the same node. What is Amazon's logic behind

来源： https://stackoverflow.com/questions/56945580/json-path-2-3-0-conflicts-with-hadoop-2-7-environment-json-smart1-2-0-jar

问题 I am using spark-sql-2.4.1v which is using hadoop-2.6.5.jar version . I need to save my data first on hdfs and move to cassandra later. Hence I am trying to save the data on hdfs as below: String hdfsPath = "/user/order_items/"; cleanedDs.createTempViewOrTable("source_tab"); givenItemList.parallelStream().forEach( item -> { String query = "select $item as itemCol , avg($item) as mean groupBy year"; Dataset<Row> resultDs = sparkSession.sql(query); saveDsToHdfs(hdfsPath, resultDs ); }); public

问题 I am confused about reading a complex file (i.e. tuple and bag) in Pig and defining schemas, to be more precise how I shall translate { , (, and a deliminator (e.g. |) during reading a file. For example, I cannot figure out the content of 'complex_7.txt' with the following line in Pig: (I am doing a reverse Eng, I have this example, and I am trying to write the text file that this schema can be used on) a = LOAD '/user/maria_dev/complex_7.txt' AS (f1:int,f2:int,B:bag{T:tuple(t1:int,t2:int)});

问题 I am confused about reading a complex file (i.e. tuple and bag) in Pig and defining schemas, to be more precise how I shall translate { , (, and a deliminator (e.g. |) during reading a file. For example, I cannot figure out the content of 'complex_7.txt' with the following line in Pig: (I am doing a reverse Eng, I have this example, and I am trying to write the text file that this schema can be used on) a = LOAD '/user/maria_dev/complex_7.txt' AS (f1:int,f2:int,B:bag{T:tuple(t1:int,t2:int)});