[atguigu@hadoop102 hadoop-2.7.2]$ bin/hadoop distcp
hdfs://haoop102:9000/user/atguigu/hello.txt hdfs://hadoop103:9000/user/atguigu/hello.txt
3. 案例实操 (1)需要启动YARN进程
[atguigu@hadoop102 hadoop-2.7.2]$ start-yarn.sh
(2)归档文件 把/user/atguigu/input目录里面的所有文件归档成一个叫input.har的归档文件,并把归档后文件存储到/user/atguigu/output路径下。
[atguigu@hadoop102 hadoop-2.7.2]$ bin/hadoop archive -archiveName input.har –p /user/atguigu/input /user/atguigu/output
(3)查看归档
[atguigu@hadoop102 hadoop-2.7.2]$ hadoop fs -lsr /user/atguigu/output/input.har
[atguigu@hadoop102 hadoop-2.7.2]$ hadoop fs -lsr har:///user/atguigu/output/input.har
(4)解归档文件 [atguigu@hadoop102 hadoop-2.7.2]$ hadoop fs -cp har:/// user/atguigu/output/input.har/* /user/atguigu
开启回收站功能,可以将删除的文件在不超时的情况下,恢复原数据,起到防止误删除、备份等作用。
<property>
<name>fs.trash.interval</name>
<value>1</value>
</property>
<property>
<name>hadoop.http.staticuser.user</name>
<value>atguigu</value>
</property>
[atguigu@hadoop102 hadoop-2.7.2]$ hadoop fs -mv
/user/atguigu/.Trash/Current/user/atguigu/input /user/atguigu/input
[atguigu@hadoop102 hadoop-2.7.2]$ hadoop fs -expunge
2. 案例实操 (1)开启/禁用指定目录的快照功能
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfsadmin -allowSnapshot /user/atguigu/input
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfsadmin -disallowSnapshot /user/atguigu/input
(2)对目录创建快照
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfs -createSnapshot /user/atguigu/input
通过web访问hdfs://hadoop102:50070/user/atguigu/input/.snapshot/s……// 快照和源文件使用相同数据
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfs -lsr /user/atguigu/input/.snapshot/
(3)指定名称创建快照
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfs -createSnapshot /user/atguigu/input miao170508
(4)重命名快照
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfs -renameSnapshot /user/atguigu/input/ miao170508 atguigu170508
(5)列出当前用户所有可快照目录
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs lsSnapshottableDir
(6)比较两个快照目录的不同之处
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs snapshotDiff
/user/atguigu/input/ . .snapshot/atguigu170508
(7)恢复快照
[atguigu@hadoop102 hadoop-2.7.2]$ hdfs dfs -cp
/user/atguigu/input/.snapshot/s20170708-134303.027 /user