CentOs7 安装Hadoop-3.1.0集群环境
虚拟机准备
master 172.16.20.11
slave1 172.16.20.12
slave2 172.16.20.13安装JDK
version 1.8.0_121，注意需要配置环境变量。
安装：参考https://blog.csdn.net/boonya/article/details/55506386
SSH免密登录
1、修改hostname
[root@localhost local]# hostname master
[root@localhost local]# hostname
master
[root@localhost local]#
[root@localhost local]# hostname slave1
[root@localhost local]# hostname
slave1
[root@localhost local]#
[root@localhost local]# hostname slave2
[root@localhost local]# hostname
slave2
[root@localhost local]# 2、修改/etc/hosts文件
修改这3台机器的/etc/hosts文件，在文件中添加以下内容：
172.16.20.11 master
172.16.20.12 slave1
172.16.20.13 slave2
3、ping验证
[root@localhost local]# ping -c 3 slave1
PING slave1 (172.16.20.11) 56(84) bytes of data.
64 bytes from master (172.16.20.11): icmp_seq=1 ttl=64 time=0.058 ms
64 bytes from master (172.16.20.11): icmp_seq=2 ttl=64 time=0.047 ms
64 bytes from master (172.16.20.11): icmp_seq=3 ttl=64 time=0.058 ms
--- slave1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.047/0.054/0.058/0.008 ms
[root@localhost local]#
4、每个机器生成秘钥文件
秘钥生成命令：ssh-keygen -t rsa -P ''
root秘钥文件保存目录：/root/.ssh/
查看秘钥：cd /root/.ssh/ 里面包含如下文件：id_rsa id_rsa.pub known_hosts
5、创建authorized_keys
在3台机器的/root/.ssh/目录下都存入一个内容相同的文件，文件名称叫authorized_keys
合并每个节点生成的id_rsa.pub到authorized_keys
authorized_keys内容:
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDwyWE1fa07nuDV0lcpczMktjX76B2TkjRyirTf4jUB9nQKneWWdCu4tUoTmlMkuG3TRt4gHLxNFbdGUK0nO7rbczUm2AdQwUNmVJKGiBk9A9AYkqbjgB8k3J0cv7PAutVHF+R0jsPArYH0FmDugAS2T24GIPNfOIu+HBsU3qlGwo8/SKiAUifO9xd7znDNBdjEptCp/9ZFB9MJN0XKLx8LG1c2nfduQBjG0UqtWjryB3GnGgaKVIGIdHW4pcZ5YYkrLqhRmjscxUmCHdHWe40fpt0J2Bt9j3LCGmuNkK3+9p3zlChPKhM8zTZW6NDLuBToZxBJFBGbWMQUag2YHVVT root@master
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCs6RYt1z/JZrXaAXfinffEH8pYzZc11vmNQ7QvSXnBFGeGvHVX/vQhwXgoIONdYyz4pCDUnyWa1d2sbEmq+gN+Dg1I1CPb6kBP5ZZuah5A1IuIFzN+OUU0UqaKnjv+WGJdf4HmxiVy6VUQsMKxoLifQFxIqfn30+KGPwN9yKS5NPG/eJrUPoUtrxumLiQ9tS3H5NWKwE86Uock1VIxOoZx6SjuoqynoIZb5i24wiN0k+DeyrYQJaPj3+vyTv9M1XFGgjMUxhBYXTNhBjMTUEY03K3ytWxBozH0Ffto9ITHFUQ0ax/92YtMPOE87e7Sp4DRILjmPnu9WahS6SISfRp9 root@slave1
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCyjeMfF92+Wvus9JdatBCGR6jKN+ZZvehDQ08fxIhcbWBymKNzz6HkS6puHFFj3aM9lFW6cE2+/pR6CLi/tQ8tGZTOm1eAjv+RwKGZvckjyE080ZfhRgjM4zy4NcF3udM1Dd4y4nPEb2h8E+ZmTL2KALuYYeDgliQQ/1TDDxtJFPxUV/R5Ul8tZZtIuyFyZJtv60NmYDkzvjcmG80OQmJkFH7jlPrErdYQORTYraDC8aLF2QJ8FnbxkYcNStKjkcuSEyBv26fE/dXO3wZD04IDS8RE35Zd0aome/8OKkQfe19LORRJne3AyM9V1xxl7cXUQxLEikvpIV33KnH8Dy0X root@slave2
6、测试SSH无密访问
[root@localhost .ssh]# ssh slave1
The authenticity of host 'slave1 (172.16.20.11)' can't be established.
ECDSA key fingerprint is ab:fb:8a:69:f0:ab:2f:3b:c4:1e:74:85:93:19:49:7c.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'slave1' (ECDSA) to the list of known hosts.
Last login: Fri Jun 15 02:33:51 2018 from master
[root@master ~]#
注意：每次ssh完成后，都要执行exit，否则你的后续命令是在另外一台机器上执行的。
[root@localhost .ssh]# ssh slave2
The authenticity of host 'slave2 (172.16.20.11)' can't be established.
ECDSA key fingerprint is ab:fb:8a:69:f0:ab:2f:3b:c4:1e:74:85:93:19:49:7c.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'slave2,172.16.20.11' (ECDSA) to the list of known hosts.
Last login: Fri Jun 15 02:05:25 2018 from 172.16.22.31
[root@master ~]#
注意：每次ssh完成后，都要执行exit，否则你的后续命令是在另外一台机器上执行的。
Hadoop安装配置
version 3.1.0，下载地址：http://hadoop.apache.org/releases.html#Download
1、上传：
分别创建/opt/hadoop目录:mkdir /opt/hadoop,cd /opt/hadoop进入目录上传Hadoop安装包。
2、解压：
tar -zxvf hadoop-3.1.0.tar.gz
3、分别在/root目录下新建几个目录，复制粘贴执行下面的命令：
mkdir /root/hadoop
mkdir /root/hadoop/tmp
mkdir /root/hadoop/var
mkdir /root/hadoop/dfs
mkdir /root/hadoop/dfs/name
mkdir /root/hadoop/dfs/data
4、分别配置Hadoop环境变量
在/etc/profile中添加如下代码
export HADOOP_HOME=/opt/hadoop/hadoop-3.1.0
export PATH=$PATH:$HADOOP_HOME/bin使修改生效
source /etc/profile
Hadoop修改配置和测试
下面开始修改master主机cd /opt/hadoop/hadoop-3.1.0/etc/hadoop目录内的一系列文件，然后将此目录拷贝到其他两个机器。
1、修改vi /opt/hadoop/hadoop-3.1.0/etc/hadoop/core-site.xml文件
在
hadoop.tmp.dir
/root/hadoop/tmp
Abase for other temporary directories.
fs.default.name
hdfs://master:9000
2、 修改/opt/hadoop/hadoop-3.1.0/etc/hadoop/hadoop-env.sh文件
添加如下JDK配置：
export JAVA_HOME=${JAVA_HOME}配置JDK安装目录。
3、 修改vi /opt/hadoop/hadoop-3.1.0/etc/hadoop/hdfs-site.xml文件
在
dfs.namenode.http-address
master:50070
dfs.name.dir
/root/hadoop/dfs/name
Path on the local filesystem where theNameNode stores the namespace and transactions logs persistently.
dfs.data.dir
/root/hadoop/dfs/data
Comma separated list of paths on the localfilesystem of a DataNode where it should store its blocks.
dfs.replication
2
dfs.permissions
true
need not permissions
说明：dfs.permissions配置为false后，可以允许不要检查权限就生成dfs上的文件，方便倒是方便了，但是你需要防止误删除，请将它设置为true，或者直接将该property节点删除，因为默认就是true。
4、修改mapred-site.xml文件，在
mapred.job.tracker
master:49001
mapred.local.dir
/root/hadoop/var
mapreduce.framework.name
yarn
5、 修改vi /opt/hadoop/hadoop-3.1.0/etc/hadoop/workers文件，将里面的localhost删除，添加如下内容：
slave1
slave26、 修改/opt/hadoop/hadoop-3.1.0/etc/hadoop/yarn-site.xml文件
在
yarn.resourcemanager.hostname
master
The address of the applications manager interface in the RM.
yarn.resourcemanager.address
${yarn.resourcemanager.hostname}:8032
The address of the scheduler interface.
yarn.resourcemanager.scheduler.address
${yarn.resourcemanager.hostname}:8030
The http address of the RM web application.
yarn.resourcemanager.webapp.address
${yarn.resourcemanager.hostname}:8088
The https adddress of the RM web application.
yarn.resourcemanager.webapp.https.address
${yarn.resourcemanager.hostname}:8090
yarn.resourcemanager.resource-tracker.address
${yarn.resourcemanager.hostname}:8031
The address of the RM admin interface.
yarn.resourcemanager.admin.address
${yarn.resourcemanager.hostname}:8033
yarn.nodemanager.aux-services
mapreduce_shuffle
yarn.scheduler.maximum-allocation-mb
2048
每个节点可用内存,单位MB,默认8182MB
yarn.nodemanager.vmem-pmem-ratio
2.1
yarn.nodemanager.resource.memory-mb
2048
yarn.nodemanager.vmem-check-enabled
false
说明：yarn.nodemanager.vmem-check-enabled这个的意思是忽略虚拟内存的检查，如果你是安装在虚拟机上，这个配置很有用，配上去之后后续操作不容易出问题。如果是实体机上，并且内存够多，可以将这个配置去掉。
7、初始化hadoop-master-只需要操作主节点(master)即可
master namenode
slave1 datanode
slave2 datanode
进入Hadoop可执行目录：cd /opt/hadoop/hadoop-3.1.0/bin
初始化命令：./hadoop namenode -format
======输出：================
[root@localhost bin]# ./hadoop namenode -format
WARNING: Use of this script to execute namenode is deprecated.
WARNING: Attempting to execute replacement "hdfs namenode" instead.
WARNING: /opt/hadoop/hadoop-3.1.0/logs does not exist. Creating.
2018-06-15 03:52:43,865 INFO namenode.NameNode: STARTUP_MSG:
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG: host = master/172.16.20.11
STARTUP_MSG: args = [-format]
STARTUP_MSG: version = 3.1.0
STARTUP_MSG: classpath = /opt/hadoop/hadoop-3.1.0/etc/hadoop:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/httpcore-4.4.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-util-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-core-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/mockito-all-1.8.5.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-core-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-crypto-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/accessors-smart-1.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/stax2-api-3.1.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-simplekdc-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerby-asn1-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jersey-server-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/guava-11.0.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-servlet-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-lang-2.6.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/httpclient-4.5.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jaxb-impl-2.2.3-1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jsch-0.1.54.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-mapper-asl-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-cli-1.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-io-2.5.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-identity-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/xz-1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/slf4j-log4j12-1.7.25.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-server-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerby-config-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/avro-1.7.7.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-math3-3.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/javax.servlet-api-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/log4j-1.2.17.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-annotations-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-io-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/paranamer-2.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/junit-4.11.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-xml-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-http-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jettison-1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/hadoop-auth-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-beanutils-1.9.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jsr305-3.0.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-server-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/token-provider-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-common-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-compress-1.4.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-configuration2-2.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/curator-recipes-2.12.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-jaxrs-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-webapp-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-xc-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-core-asl-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/curator-client-2.12.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/curator-framework-2.12.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jetty-security-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/zookeeper-3.4.9.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-net-3.6.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/woodstox-core-5.0.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jersey-json-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/hadoop-annotations-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/gson-2.2.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/htrace-core4-4.1.0-incubating.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/snappy-java-1.0.5.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/slf4j-api-1.7.25.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/json-smart-2.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/netty-3.10.5.Final.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/asm-5.0.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-collections-3.2.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jersey-core-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jersey-servlet-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-util-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerby-pkix-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jsr311-api-1.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/nimbus-jose-jwt-4.41.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-client-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerb-admin-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-codec-1.11.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/re2j-1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-logging-1.1.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerby-xdr-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/metrics-core-3.2.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jcip-annotations-1.0-1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jackson-databind-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/hamcrest-core-1.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/kerby-util-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jsp-api-2.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jul-to-slf4j-1.7.25.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/protobuf-java-2.5.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/jaxb-api-2.2.11.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/lib/commons-lang3-3.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/hadoop-common-3.1.0-tests.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/hadoop-kms-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/hadoop-common-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/common/hadoop-nfs-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/httpcore-4.4.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-util-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-core-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-core-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/json-simple-1.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-crypto-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/accessors-smart-1.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/stax2-api-3.1.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-simplekdc-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerby-asn1-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jersey-server-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/guava-11.0.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-servlet-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-lang-2.6.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/httpclient-4.5.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jaxb-impl-2.2.3-1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jsch-0.1.54.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-mapper-asl-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-cli-1.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-io-2.5.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-identity-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/xz-1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-daemon-1.0.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-server-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerby-config-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/avro-1.7.7.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-math3-3.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/javax.servlet-api-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/log4j-1.2.17.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-annotations-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-io-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/paranamer-2.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-xml-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-http-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jettison-1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/hadoop-auth-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-beanutils-1.9.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jsr305-3.0.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/leveldbjni-all-1.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-server-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/token-provider-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-common-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-compress-1.4.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-configuration2-2.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/curator-recipes-2.12.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-jaxrs-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-webapp-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-xc-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-core-asl-1.9.13.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/curator-client-2.12.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/okio-1.6.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/curator-framework-2.12.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-security-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/zookeeper-3.4.9.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-net-3.6.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/woodstox-core-5.0.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jersey-json-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/hadoop-annotations-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/gson-2.2.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/htrace-core4-4.1.0-incubating.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/snappy-java-1.0.5.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/json-smart-2.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/netty-3.10.5.Final.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/asm-5.0.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-collections-3.2.2.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jersey-core-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/okhttp-2.7.5.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jersey-servlet-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-util-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/netty-all-4.0.52.Final.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerby-pkix-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jsr311-api-1.1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/nimbus-jose-jwt-4.41.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-client-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jetty-util-ajax-9.3.19.v20170502.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerb-admin-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-codec-1.11.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/re2j-1.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-logging-1.1.3.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerby-xdr-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jcip-annotations-1.0-1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jackson-databind-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/kerby-util-1.0.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/protobuf-java-2.5.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/jaxb-api-2.2.11.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/lib/commons-lang3-3.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-httpfs-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-rbf-3.1.0-tests.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-3.1.0-tests.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-native-client-3.1.0-tests.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-rbf-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-client-3.1.0-tests.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-native-client-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-client-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-nfs-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/hdfs/hadoop-hdfs-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-common-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-shuffle-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-3.1.0-tests.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-app-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-hs-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-hs-plugins-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-nativetask-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-core-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-examples-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/mapreduce/hadoop-mapreduce-client-uploader-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/javax.inject-1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/snakeyaml-1.16.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/jackson-jaxrs-json-provider-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/jackson-jaxrs-base-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/guice-servlet-4.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/swagger-annotations-1.5.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/json-io-2.5.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/jersey-guice-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/aopalliance-1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/jersey-client-1.19.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/mssql-jdbc-6.2.1.jre7.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/geronimo-jcache_1.0_spec-1.0-alpha-1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/fst-2.50.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/java-util-1.9.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/guice-4.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/jackson-module-jaxb-annotations-2.7.8.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/HikariCP-java7-2.4.12.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/metrics-core-3.2.4.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/ehcache-3.3.1.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/lib/dnsjava-2.1.7.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-timeline-pluginstorage-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-common-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-common-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-services-core-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-applications-distributedshell-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-client-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-applications-unmanaged-am-launcher-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-registry-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-applicationhistoryservice-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-router-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-nodemanager-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-tests-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-sharedcachemanager-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-api-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-web-proxy-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-services-api-3.1.0.jar:/opt/hadoop/hadoop-3.1.0/share/hadoop/yarn/hadoop-yarn-server-resourcemanager-3.1.0.jar
STARTUP_MSG: build = https://github.com/apache/hadoop -r 16b70619a24cdcf5d3b0fcf4b58ca77238ccbe6d; compiled by 'centos' on 2018-03-30T00:00Z
STARTUP_MSG: java = 1.8.0_121
************************************************************/
2018-06-15 03:52:43,993 INFO namenode.NameNode: registered UNIX signal handlers for [TERM, HUP, INT]
2018-06-15 03:52:44,142 INFO namenode.NameNode: createNameNode [-format]
2018-06-15 03:52:48,834 WARN common.Util: Path /root/hadoop/dfs/name should be specified as a URI in configuration files. Please update hdfs configuration.
2018-06-15 03:52:48,836 WARN common.Util: Path /root/hadoop/dfs/name should be specified as a URI in configuration files. Please update hdfs configuration.
Formatting using clusterid: CID-b68f9bc2-8813-4fef-8e98-903e82769d41
2018-06-15 03:52:48,944 INFO namenode.FSEditLog: Edit logging is async:true
2018-06-15 03:52:49,207 INFO namenode.FSNamesystem: KeyProvider: null
2018-06-15 03:52:49,208 INFO namenode.FSNamesystem: fsLock is fair: true
2018-06-15 03:52:49,210 INFO namenode.FSNamesystem: Detailed lock hold time metrics enabled: false
2018-06-15 03:52:49,254 INFO namenode.FSNamesystem: fsOwner = root (auth:SIMPLE)
2018-06-15 03:52:49,254 INFO namenode.FSNamesystem: supergroup = supergroup
2018-06-15 03:52:49,267 INFO namenode.FSNamesystem: isPermissionEnabled = true
2018-06-15 03:52:49,268 INFO namenode.FSNamesystem: HA Enabled: false
2018-06-15 03:52:49,359 INFO common.Util: dfs.datanode.fileio.profiling.sampling.percentage set to 0. Disabling file IO profiling
2018-06-15 03:52:49,393 INFO blockmanagement.DatanodeManager: dfs.block.invalidate.limit: configured=1000, counted=60, effected=1000
2018-06-15 03:52:49,393 INFO blockmanagement.DatanodeManager: dfs.namenode.datanode.registration.ip-hostname-check=true
2018-06-15 03:52:49,410 INFO blockmanagement.BlockManager: dfs.namenode.startup.delay.block.deletion.sec is set to 000:00:00:00.000
2018-06-15 03:52:49,410 INFO blockmanagement.BlockManager: The block deletion will start around 2018 Jun 15 03:52:49
2018-06-15 03:52:49,413 INFO util.GSet: Computing capacity for map BlocksMap
2018-06-15 03:52:49,414 INFO util.GSet: VM type = 64-bit
2018-06-15 03:52:49,430 INFO util.GSet: 2.0% max memory 407.5 MB = 8.1 MB
2018-06-15 03:52:49,430 INFO util.GSet: capacity = 2^20 = 1048576 entries
2018-06-15 03:52:49,470 INFO blockmanagement.BlockManager: dfs.block.access.token.enable = false
2018-06-15 03:52:49,531 INFO Configuration.deprecation: No unit for dfs.namenode.safemode.extension(30000) assuming MILLISECONDS
2018-06-15 03:52:49,532 INFO blockmanagement.BlockManagerSafeMode: dfs.namenode.safemode.threshold-pct = 0.9990000128746033
2018-06-15 03:52:49,532 INFO blockmanagement.BlockManagerSafeMode: dfs.namenode.safemode.min.datanodes = 0
2018-06-15 03:52:49,532 INFO blockmanagement.BlockManagerSafeMode: dfs.namenode.safemode.extension = 30000
2018-06-15 03:52:49,532 INFO blockmanagement.BlockManager: defaultReplication = 2
2018-06-15 03:52:49,532 INFO blockmanagement.BlockManager: maxReplication = 512
2018-06-15 03:52:49,532 INFO blockmanagement.BlockManager: minReplication = 1
2018-06-15 03:52:49,533 INFO blockmanagement.BlockManager: maxReplicationStreams = 2
2018-06-15 03:52:49,533 INFO blockmanagement.BlockManager: redundancyRecheckInterval = 3000ms
2018-06-15 03:52:49,533 INFO blockmanagement.BlockManager: encryptDataTransfer = false
2018-06-15 03:52:49,533 INFO blockmanagement.BlockManager: maxNumBlocksToLog = 1000
2018-06-15 03:52:49,806 INFO util.GSet: Computing capacity for map INodeMap
2018-06-15 03:52:49,807 INFO util.GSet: VM type = 64-bit
2018-06-15 03:52:49,807 INFO util.GSet: 1.0% max memory 407.5 MB = 4.1 MB
2018-06-15 03:52:49,807 INFO util.GSet: capacity = 2^19 = 524288 entries
2018-06-15 03:52:50,059 INFO namenode.FSDirectory: ACLs enabled? false
2018-06-15 03:52:50,059 INFO namenode.FSDirectory: POSIX ACL inheritance enabled? true
2018-06-15 03:52:50,059 INFO namenode.FSDirectory: XAttrs enabled? true
2018-06-15 03:52:50,060 INFO namenode.NameNode: Caching file names occurring more than 10 times
2018-06-15 03:52:50,069 INFO snapshot.SnapshotManager: Loaded config captureOpenFiles: false, skipCaptureAccessTimeOnlyChange: false, snapshotDiffAllowSnapRootDescendant: true, maxSnapshotLimit: 65536
2018-06-15 03:52:50,077 INFO snapshot.SnapshotManager: SkipList is disabled
2018-06-15 03:52:50,095 INFO util.GSet: Computing capacity for map cachedBlocks
2018-06-15 03:52:50,095 INFO util.GSet: VM type = 64-bit
2018-06-15 03:52:50,095 INFO util.GSet: 0.25% max memory 407.5 MB = 1.0 MB
2018-06-15 03:52:50,096 INFO util.GSet: capacity = 2^17 = 131072 entries
2018-06-15 03:52:50,119 INFO metrics.TopMetrics: NNTop conf: dfs.namenode.top.window.num.buckets = 10
2018-06-15 03:52:50,119 INFO metrics.TopMetrics: NNTop conf: dfs.namenode.top.num.users = 10
2018-06-15 03:52:50,119 INFO metrics.TopMetrics: NNTop conf: dfs.namenode.top.windows.minutes = 1,5,25
2018-06-15 03:52:50,138 INFO namenode.FSNamesystem: Retry cache on namenode is enabled
2018-06-15 03:52:50,138 INFO namenode.FSNamesystem: Retry cache will use 0.03 of total heap and retry cache entry expiry time is 600000 millis
2018-06-15 03:52:50,150 INFO util.GSet: Computing capacity for map NameNodeRetryCache
2018-06-15 03:52:50,151 INFO util.GSet: VM type = 64-bit
2018-06-15 03:52:50,151 INFO util.GSet: 0.029999999329447746% max memory 407.5 MB = 125.2 KB
2018-06-15 03:52:50,151 INFO util.GSet: capacity = 2^14 = 16384 entries
2018-06-15 03:52:50,214 INFO namenode.FSImage: Allocated new BlockPoolId: BP-1573278845-172.16.20.11-1529049170199
2018-06-15 03:52:50,242 INFO common.Storage: Storage directory /root/hadoop/dfs/name has been successfully formatted.
2018-06-15 03:52:50,273 INFO namenode.FSImageFormatProtobuf: Saving image file /root/hadoop/dfs/name/current/fsimage.ckpt_0000000000000000000 using no compression
2018-06-15 03:52:50,459 INFO namenode.FSImageFormatProtobuf: Image file /root/hadoop/dfs/name/current/fsimage.ckpt_0000000000000000000 of size 389 bytes saved in 0 seconds .
2018-06-15 03:52:50,482 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0
2018-06-15 03:52:50,546 INFO namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at master/172.16.20.11
************************************************************/
[root@localhost bin]#
格式化成功后，可以在看到在/root/hadoop/dfs/name/目录多了一个current
8、启动namenode：hadoop-master
进入指令操作：cd /opt/hadoop/hadoop-3.1.0/sbin
执行指令： ./start-all.sh
启动失败：
[root@localhost sbin]# ./start-all.sh
Starting namenodes on [master]
ERROR: Attempting to operate on hdfs namenode as root
ERROR: but there is no HDFS_NAMENODE_USER defined. Aborting operation.
Starting datanodes
ERROR: Attempting to operate on hdfs datanode as root
ERROR: but there is no HDFS_DATANODE_USER defined. Aborting operation.
Starting secondary namenodes [master]
ERROR: Attempting to operate on hdfs secondarynamenode as root
ERROR: but there is no HDFS_SECONDARYNAMENODE_USER defined. Aborting operation.
Starting resourcemanager
ERROR: Attempting to operate on yarn resourcemanager as root
ERROR: but there is no YARN_RESOURCEMANAGER_USER defined. Aborting operation.
Starting nodemanagers
ERROR: Attempting to operate on yarn nodemanager as root
ERROR: but there is no YARN_NODEMANAGER_USER defined. Aborting operation.
[root@localhost sbin]#
解决失败方案（参考：https://blog.csdn.net/lglglgl/article/details/80553828）：
master，slave都需要修改start-dfs.sh，stop-dfs.sh，start-yarn.sh，stop-yarn.sh四个文件
将start-dfs.sh，stop-dfs.sh两个文件顶部添加以下参数
#!/usr/bin/env bash
HDFS_DATANODE_USER=root
HADOOP_SECURE_DN_USER=hdfs
HDFS_NAMENODE_USER=root
HDFS_SECONDARYNAMENODE_USER=rootstart-yarn.sh，stop-yarn.sh顶部也需添加以下：
#!/usr/bin/env bash
YARN_RESOURCEMANAGER_USER=root
HADOOP_SECURE_DN_USER=yarn
YARN_NODEMANAGER_USER=root
WARNING: HADOOP_SECURE_DN_USER has been replaced by HDFS_DATANODE_SECURE_USER. Using value of HADOOP_SECURE_DN_USER.
将start-dfs.sh，stop-dfs.sh两个文件顶部添加以下参数
#!/usr/bin/env bash
HDFS_DATANODE_USER=root
HDFS_DATANODE_SECURE_USER=hdfs
HDFS_NAMENODE_USER=root
HDFS_SECONDARYNAMENODE_USER=root
start-yarn.sh，stop-yarn.sh顶部也需添加以下：
#!/usr/bin/env bash
YARN_RESOURCEMANAGER_USER=root
HDFS_DATANODE_SECURE_USER=yarn
YARN_NODEMANAGER_USER=root9、复制/opt/hadoop到salve1和slave2节点
scp -r /opt/hadoop slave1:/opt/
scp -r /opt/hadoop slave2:/opt/10、浏览器访问（访问不到时请关闭master的防火墙systemctl stop firewalld.service）：
节点监控：http://172.16.20.11:50070/
查看资源：http://172.16.20.11:8088/
配置不出来可以参考以下文章：
Linux上安装Hadoop集群(CentOS7+hadoop-2.8.0)
centos7下hadoop-3.1.0集群搭建
Hadoop3.1.0完全分布式集群部署超详细记录
此处提供一组集群下载:https://pan.baidu.com/s/1yvC7eQx_UFYuzgLbTNTw6Q
如有问题请参考：
Hadoop 集群多次格式化导致容量分配为0不能导入数据
Hadoop运行默认提供的字数统计示例