WedHDFS配置及使用方法整理

WedHDFS配置及使用方法

一、配置

1、修改hadoop配置文件hdfs-site.xml，添加：

<property>
<name>dfs.webhdfs.enabled</name>
<value>true</value>
</property>

注：此配置在集群中所以机器上都需要修改

2、同样配置hdfs-site.xml文件，添加：

<property>
<name>dfs.permissions</name>
<value>false</value>
</property>

注：此配置在集群中所以机器上都需要修改

二、curl操作hadoop hdfs

1、创建并写一个文件

注意这个地方填入的是DataNode的信息

注意该条命令获得的是DataNode的信息。

[&offset=<LONG>][&length=<LONG>][&buffersize=<INT>]“

curl -i -X PUT "http://<HOST>:<PORT>/<PATH>?op=MKDIRS[&permission=<OCTAL>]“

curl -i -X PUT "<HOST>:<PORT>/webhdfs/v1/<PATH>?op=RENAME&destination=<PATH>"

curl -i -X DELETE "http://<host>:<port>/webhdfs/v1/<path>?op=DELETE [&recursive=<true|false>]“

curl -i “http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=GETFILESTATUS“

curl -i "http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=LISTSTATUS”

curl -i "http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=GETCONTENTSUMMARY"

curl -i "http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=GETFILECHECKSUM”

curl -i "http://<HOST>:<PORT>/webhdfs/v1/?op=GETHOMEDIRECTORY”

curl -i -X PUT "http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=SETPERMISSION [&permission=<OCTAL>]“

curl -i -X PUT "http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=SETOWNER [&owner=<USER>][&group=<GROUP>]"

14、设置备份

curl -i -X PUT "http://<HOST>:<PORT>/webhdfs/v1/<PATH>?op=SETREPLICATION [&replication=<SHORT>]“

三、错误信息分析

1、URL问题，如：上传文件

[root@Client04 qzhang]# curl -i -X PUT "http://xx.xx.xx.xx:50070/webhdfs/v1/qzhang?op=CREATE"

HTTP/1.1 307 TEMPORARY_REDIRECT

Cache-Control: no-cache

Expires: Mon, 21 Oct 2013 03:25:55 GMT

Date: Mon, 21 Oct 2013 03:25:55 GMT

Pragma: no-cache

Expires: Mon, 21 Oct 2013 03:25:55 GMT

Date: Mon, 21 Oct 2013 03:25:55 GMT

Pragma: no-cache

Content-Type: application/octet-stream

Location: http://Slave01:50075/webhdfs/v1/qzhang?op=CREATE&namenoderpcaddress=Master:9100&overwrite=false

Content-Length: 0

Server: Jetty(6.1.26)

[root@Client04 qzhang]# curl -i -X PUT -T '/home/qzhang/桌面/mapred-site.xml' "http://Slave01:50075/webhdfs/v1/qzhang/mapred-site.xml?op=CREATE&namenoderpcaddress=Master:9100&overwrite=false"

HTTP/1.1 100 Continue

HTTP/1.1 405 HTTP method PUT is not supported by this URL

Date: Mon, 21 Oct 2013 03:27:45 GMT

Pragma: no-cache

Date: Mon, 21 Oct 2013 03:27:45 GMT

Pragma: no-cache

Content-Length: 0

Server: Jetty(6.1.26)

错误分析：datanode Slave01上没有配置好hdfs-site.xml文件，webhdfs不可用。必须集群所有机器配置好webhdfs，因为文件直接上传到datanode。

2、权限问题

[root@Client04 qzhang]# curl -i -X PUT -T '/home/qzhang/桌面/mapred-site.xml' "http://Slave02:50075/webhdfs/v1/qzhang/mapred-site.xml?op=CREATE&namenoderpcaddress=Master:9100&overwrite=false"

HTTP/1.1 100 Continue

HTTP/1.1 403 Forbidden

Cache-Control: no-cache

Expires: Mon, 21 Oct 2013 03:05:25 GMT

Date: Mon, 21 Oct 2013 03:05:25 GMT

Pragma: no-cache

Expires: Mon, 21 Oct 2013 03:05:25 GMT

Date: Mon, 21 Oct 2013 03:05:25 GMT

Pragma: no-cache

Content-Type: application/json

Transfer-Encoding: chunked

Server: Jetty(6.1.26)

{"RemoteException":{"exception":"AccessControlException","javaClassName":"org.apache.hadoop.security.AccessControlException","message":"Permission denied: user=dr.who, access=WRITE, inode=\"/qzhang\":Administrator:supergroup:drwxr-xr-x\n\tat org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.check(FSPermissionChecker.java:234)\n\tat org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.check(FSPermissionChecker.java:214)\n\tat org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkPermission(FSPermissionChecker.java:158)\n\tat org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:5178)\n\tat org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:5160)\n\tat org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkAncestorAccess(FSNamesystem.java:5134)\n\tat org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInternal(FSNamesystem.java:2054)\n\tat org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInt(FSNamesystem.java:2007)\n\tat org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFile(FSNamesystem.java:1958)\n\tat org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.create(NameNodeRpcServer.java:491)\n\tat org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.create(ClientNamenodeProtocolServerSideTranslatorPB.java:301)\n\tat org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java:59570)\n\tat org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:585)\n\tat org.apache.hadoop.ipc.RPC$Server.call(RPC.java:928)\n\tat org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2048)\n\tat org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2044)\n\tat java.security.AccessController.doPrivileged(Native Method)\n\tat javax.security.auth.Subject.doAs(Subject.java:415)\n\tat org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1483)\n\tat org.apache.hadoop.ipc.Server$Handler.run(Server.java:2042)\n"}}

错误分析：集群外机器没有访问hdfs的权限，可以配置hdfs-site.xml，即配置中的第2步，关闭hdfs的权限