网上拉取Docker模板，使用singlarities/hadoop镜像
[root@localhost /]# docker pull singularities/hadoop
查看：
[root@localhost /]# docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
docker.io/singularities/hadoop latest e213c9ae1b36 months ago 1.19 GB
创建docker-compose.yml文件，内容：
version: "" services:
namenode:
image: singularities/hadoop
command: start-hadoop namenode
hostname: namenode
environment:
HDFS_USER: hdfsuser
ports:
- "8020:8020"
- "14000:14000"
- "50070:50070"
- "50075:50075"
- "10020:10020"
- "13562:13562"
- "19888:19888"
datanode:
image: singularities/hadoop
command: start-hadoop datanode namenode
environment:
HDFS_USER: hdfsuser
links:
- namenode
执行：
[root@localhost hadoop]# docker-compose up -d
Creating network "hadoop_default" with the default driver
Creating hadoop_namenode_1 ... done
Creating hadoop_datanode_1 ... done
4个datanode:
[root@localhost hadoop]# docker-compose scale datanode=
WARNING: The scale command is deprecated. Use the up command with the --scale flag instead.
Starting hadoop_datanode_1 ... done
Creating hadoop_datanode_2 ... done
Creating hadoop_datanode_3 ... done
[root@localhost hadoop]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
19f9685e286f singularities/hadoop "start-hadoop data..." seconds ago Up seconds /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp hadoop_datanode_3
e96b395f56e3 singularities/hadoop "start-hadoop data..." seconds ago Up seconds /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp hadoop_datanode_2
5a26b1069dbb singularities/hadoop "start-hadoop data..." minutes ago Up minutes /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp, /tcp hadoop_datanode_1
a8656de09ecc singularities/hadoop "start-hadoop name..." minutes ago Up minutes 0.0.0.0:->/tcp, 0.0.0.0:->/tcp, 0.0.0.0:->/tcp, 0.0.0.0:->/tcp, /tcp, /tcp, 0.0.0.0:->/tcp, 0.0.0.0:->/tcp, /tcp, /tcp, /tcp, 0.0.0.0:->/tcp, /tcp hadoop_namenode_1
[root@localhost hadoop]#
效果图；
hdfs基础命令：
1、创建目录
hadoop fs -mkdir /hdfs #在根目录下创建hdfs文件夹
2、查看目录
>hadoop fs -ls / #列出跟目录下的文件列表
drwxr-xr-x - root supergroup -- : /hdfs
3、级联创建目录
>hadoop fs -mkdir -p /hdfs/d1/d2
4、级联列出目录
>hadoop fs -ls -R /
drwxr-xr-x - root supergroup -- : /hdfs
drwxr-xr-x - root supergroup -- : /hdfs/d1
drwxr-xr-x - root supergroup -- : /hdfs/d1/d2
5、上传本地文件到HDFS
>echo "hello hdfs" >>local.txt
>hadoop fs -put local.txt /hdfs/d1/d2
6、查看HDFS中文件的内容
>hadoop fs -cat /hdfs/d1/d2/local.txt
hello hdfs
7、下载hdfs上文件的内容
>hadoop fs -get /hdfs/d1/d2/local.txt
8、删除hdfs文件
>hadoop fs -rm /hdfs/d1/d2/local.txt
Deleted /hdfs/d1/d2/local.txt
9、删除hdfs中目录
>hadoop fs -rmdir /hdfs/d1/d2
10、修改文件的权限
>hadoop fs -ls /hdfs
drwxr-xr-x - root supergroup -- : /hdfs/d1 #注意文件的权限
>hadoop fs -chmod /hdfs/d1
drwxrwxrwx - root supergroup -- : /hdfs/d1 #修改后
11、修改文件所属的用户
>hadoop fs -chown admin /hdfs/d1 #修改文件所属用户为admin
>hadoop fs -ls /hdfs
drwxrwxrwx - admin supergroup -- : /hdfs/d1
12、修改文件的用户组
>hadoop fs -chgrp admin /hdfs/d1
>hadoop fs -ls /hdfs
drwxrwxrwx - admin admin -- : /hdfs/d1
查看所有命令方式：
root@master:/# hadoop fs
Usage: hadoop fs [generic options]
[-appendToFile <localsrc> ... <dst>]
[-cat [-ignoreCrc] <src> ...]
[-checksum <src> ...]
[-chgrp [-R] GROUP PATH...]
[-chmod [-R] <MODE[,MODE]... | OCTALMODE> PATH...]
[-chown [-R] [OWNER][:[GROUP]] PATH...]
[-copyFromLocal [-f] [-p] [-l] [-d] <localsrc> ... <dst>]
[-copyToLocal [-f] [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
[-count [-q] [-h] [-v] [-t [<storage type>]] [-u] [-x] <path> ...]
[-cp [-f] [-p | -p[topax]] [-d] <src> ... <dst>]
[-createSnapshot <snapshotDir> [<snapshotName>]]
[-deleteSnapshot <snapshotDir> <snapshotName>]
[-df [-h] [<path> ...]]
[-du [-s] [-h] [-x] <path> ...]
[-expunge]
[-find <path> ... <expression> ...]
[-get [-f] [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
[-getfacl [-R] <path>]
[-getfattr [-R] {-n name | -d} [-e en] <path>]
[-getmerge [-nl] [-skip-empty-file] <src> <localdst>]
[-help [cmd ...]]
[-ls [-C] [-d] [-h] [-q] [-R] [-t] [-S] [-r] [-u] [<path> ...]]
[-mkdir [-p] <path> ...]
[-moveFromLocal <localsrc> ... <dst>]
[-moveToLocal <src> <localdst>]
[-mv <src> ... <dst>]
[-put [-f] [-p] [-l] [-d] <localsrc> ... <dst>]
[-renameSnapshot <snapshotDir> <oldName> <newName>]
[-rm [-f] [-r|-R] [-skipTrash] [-safely] <src> ...]
[-rmdir [--ignore-fail-on-non-empty] <dir> ...]
[-setfacl [-R] [{-b|-k} {-m|-x <acl_spec>} <path>]|[--set <acl_spec> <path>]]
[-setfattr {-n name [-v value] | -x name} <path>]
[-setrep [-R] [-w] <rep> <path> ...]
[-stat [format] <path> ...]
[-tail [-f] <file>]
[-test -[defsz] <path>]
[-text [-ignoreCrc] <src> ...]
[-touchz <path> ...]
[-truncate [-w] <length> <path> ...]
[-usage [cmd ...]] Generic options supported are
-conf <configuration file> specify an application configuration file
-D <property=value> use value for given property
-fs <file:///|hdfs://namenode:port> specify default filesystem URL to use, overrides 'fs.defaultFS' property from configurations.
-jt <local|resourcemanager:port> specify a ResourceManager
-files <comma separated list of files> specify comma separated files to be copied to the map reduce cluster
-libjars <comma separated list of jars> specify comma separated jar files to include in the classpath.
-archives <comma separated list of archives> specify comma separated archives to be unarchived on the compute machines. The general command line syntax is
command [genericOptions] [commandOptions]
进入一个容器内部进行上述操作，再进入其他的容器，可以发现数据同步了，另外一个节点的操作其他节点也可以看见。
参考：