Step 1: Create a hadoop user and authorize the hadoop user
(1) In a new Linux system CentOS-7-x86_64-DVD-1708 In the .iso, if the initial user is root and not a hadoop user, then one needs to
Tag: Hadoop
CentOS 7 Install Hadoop Cluster
Prepare three virtual machines, ip are 192.168.220.10 (master), 192.168.220.11 (slave1), 192.168.220.12 (slave2)
Ready jdk-6u45-linux- x64.bin and hadoop-1.2.1-bin.tar.gz, placed in the /usr/
Hadoop – ‘SparkContext’ Object No Properties ‘TextFile’
I tried to load the file using the following code:
textdata = sc.textfile(‘hdfs://localhost:9000 /file.txt’) Error message:
AttributeError:’SparkContext’ object has no attribute’textfil
Hadoop has one or more files per mapper?
Does the mapper process multiple files at the same time or the mapper can only process one file at a time? I want to know the default behavior >By default, a typical Mapreduce job follows one inp
Hadoop – What is the difference between FirstInfirstoutPrioritizer and OldestFlowFileFirstPrioritizer?
The user guide https://nifi.apache.org/docs/nifi-docs/html/user-guide.html has the following detailed information about the priority sorter, please help I understand these differences and provide a
Hadoop-HDFS-Storage Model – Architecture Model – Role Introduction
Why happened to hadoop spilling?
I am very new to the Hadoop system and the learning phase.
I noticed that Spill occurs as long as the MapOutputBuffer reaches 80% in the Shuffle and Sort phases (I think this can also be conf
Hadoop uses Java to set FSPERMISSION to DIR in recursive way
Hi I have a test program, load the file to hdfs user/user1/data/app/type/file.gz on this path now this test program is run multiple times by multiple users . So I want to set the file permissions t
Hadoop – How to make S3DISTCP complies with the wrap
I have millions of small one-line s3 files that I want to merge together. I have s3distcp syntax, but I found that after merging the files, the merged set does not contain newline characters.
Hadoop – Hive query stays 99%
I use left join to insert records in Hive. When I set limit 1 query, but for all record queries, it stays at 99% to reduce jobs.
Insert overwrite table tablename select a.id, b.name from a le