linux commands for hadoop administration

/directory: Create a user and then specify the user's home directoryDeleteUserdel User name: Just delete the user but do not delete the home directoryUserdel-r User name: Delete user with home directory deleteTo switch users:Ssh-l User name-P 22 HostExample: Ssh-l tom-p 22 192.168.17.131Su-user name Group ManagementAdd toGroupadd Group NameUseradd User name-G group nameDeleteGroupdel Group NameAttention:If there are users under the group, can not delete permissions for the file:Normal files: In

Special Permissions Introduction to Commands: SUID: when running a program, the owner of the corresponding process is the owner of the program file itself, not the initiator;chmod u+s FILEchmod u-s FILE If file itself has execute permission, then SUID is displayed as S;SGID: when running a program, the group of the corresponding process is the group of the program file itself, not the base group to which the initiator belongs;chmod g+s FILEchmod g-s

spark:// 100.65.32.215:8070,100.65.32.212:8070Examples of Spark SQL operations:Export Spark_classpath= $SPARK _classpath:/data/webitil/hive/lib/mysql-connector-java-5.0.8-bin.jarspark_ Classpath= $SPARK _classpath:/data/webitil/hive/lib/mysql-connector-java-5.0.8-bin.jar./spark-sql--master spark:/ /10.49.133.77:8070./spark-sql--master spark://10.49.133.77:8070--jars/data/webitil/hive/lib/ Mysql-connector-java-5.0.8-bin.jar./spark-shell--jars/data/webitil/hive/lib/mysql-connector-java-5.0.8-bin.

default permissions for newly created folders are 755Under Linux, the default permissions for newly created files are 644Learn to use Pietty, WinSCPUnzip tar.gz file TAR-ZXVF hadoop-1.1.2.tar.gz1. Installing the JDK1) Increased execution permissions chmod 777 jdk******2) unzip./jdk*******3) Rename MV jdk***** JDK4) Set environment variables, execute Vi/etc/profileAdd two rows of records export JAVA_HOME=/U

line full screen modeSystem administration Commands:Stat Displays details of the specified file, more detailed than LSWho shows online login usersWHOAMI Show current Operation userHostname Display host nameUname Display System InformationTop dynamic display currently consumes the most resources process informationPS Display transient process status Ps-auxDu view directory size Du-h/home with units display directory informationDF View disk size df-h w

replace the above command TAR-CVF/TAR-ZCVF/TAR-JCVF "C" in the "X".Shut down/Restart the machineShutdown-R shutdown Restart-H shutdown does not restartNow turn the machine off.Halt shut down the machineReboot restartVim useVim three modes: Command mode, insert mode, edit mode. Use ESC or I or: to toggle the mode.Command mode:: Q exit: q! Force exit: Wq Save and exit: Set number Displays line numbers: Set Nonumber hidden line number/apache find Apache in the document press N to jump to the next,

Tags: User copy ping string operation link file unit directory size mkdirLinux Common directives:LS display file or directory ls-l list file details ls-a lists all files or directories in the current directory, including hiddenLs-al display detailed file information, including hidden files mkdir creating a directoryMKDIR-P Create directory, if no parent directory, create parent directory CD switch directory touch create empty file echo Create file with contentCat View file contents CP Copy MV Mo

One, switch from user to root userWhether you're logging in to Ubuntu in graphical mode or in command-line mode, we'll find that the default is user, but when we need to do something with root privileges (such as a system file), we often need to use sudo to authorize it, which is a hassle, and we can switch to the root user, Simply execute sudo su.1 [email protected]:~$ sudo su2Note: For security reasons, the default Ubuntu root user does not have a fixed password, its password is randomly gener

) Options: -T: List TCP protocol ports -u: List upd protocol port -n: Do not use domain name and service name, but use IP address and port number -l: List only in the Listening State Network service -A: List all network connections -r: List of routing lists , features and route commands a common combination: -tuln, -an, -rn View network connections in a certain state, such as Netstat -an | grep established view the number of rows in a network

to other users on the system. In this case, every user in the system can access the files or directories that the user owns.Each file or directory has three groups of access rights, each group is represented by three bits, respectively, the read, write, and execute permissions of the file owner, the read, write, and execute permissions of the user belonging to the primary group, and the read, write, and execute permissions of other users in the system.Second, the use of the CHMOD,CHOWN,CHGRP co

Filesystem Hierarchy Standard (FHS)/: root directory, all directories, files, devices are in/below,/is the Linux file system Organizer, is also the most superior leader./bin:bin is the binary (binary) abbreviation. In the general system, you can find the common Linux commands in this directory. The commands required by

trend.Type: Shows which type the specified command belongs toPRINTENV: Display Environment variablesHash: Key Value Database Cache is King caching enables system acceleration Time Date: Time ManagementLinux Time Implementation mode: RTCNtp:network Time ProtocolHardware clockSoftware clockHwclock- W: Write system time to hardware-S: Write hardware time into the system Get help with the use of commands Internal command:Help

text Mode– Linux also inherits the traditional command-line-based text user environment of UNIX systems, allowing users to perform their work in an efficient environment at the command line.　　–linux Most of the work is done through console mode.　　The console of the –linux system is also known as command-line mode or Linux