linux commands for hadoop administration

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 commandAfter determining the access rights of a file, users can use the chmod command provided by the Linux system to reset different access rights. You

The purpose of this article is to introduce some people who are less known Linux commands, they are sure to help you manage your desktop / server efficiently. 1. sudo!! CommandRunning without a specific input sudo command will give you an error with no permissions. Well, you don't need to rewrite the entire command, just type ' !! ' you can grab the last command. $ apt-get UpdateE:could not open lock File/v

first, the directory structure of Linux Directory name meaning/bin common commands for Linux in this directory, in some versions the same directory as the root directory./boot This directory is stored in the system to use the program when booting, when using Lilo to boot Linux, will use some of the information here/de

The Linux command line attracts most Linux enthusiasts. A normal Linux user typically has about 50-60 commands to handle daily tasks. Linux commands and their transformations are the most valuable treasures for

Linux common Commands (iii) SSH(1) Install and configure SSH login without passwordCentOS default installed SSH client, SSH server, open the terminal to perform the following command to verifyrpm -qa | grep sshIf the returned result is as shown, the SSH client and SSH server are included, there is no need to installIf installation is required, it can be installed via Yum:yum -y install openssh-clients opens

Common Operations system Commands View Host Namehostname Modify host name (invalid after reboot)hostname Yang Modify host name (permanent after reboot)vi/ect/sysconfig/network Modify IP (invalid after reboot)ifconfig eth0 192.168.12.22 Modify IP (permanently effective after reboot)Vi/etc/sysconfig/network-scripts/ifcfg-eth0 View System Informationuname-aUname-r View ID CommandId-uId-g to see who is online (who landed on the server)Who view current o

sets the password for rootSu RootSu-root/etc/profile System Environment variablesBash_profile User Environment variables. BASHRC User Environment variablesSU user switches the user and loads the configuration file. bashrcSu-user switch User, load configuration file/etc/profile, load Bash_profileUser and user groups for changing filessudo chown [-r] Owner[:group] {file| Directory}For example: Also take jdk-7u21-linux-i586.tar.gz as an example. belongs

sets the password for rootSu RootSu-root/etc/profile System Environment variablesBash_profile User Environment variables. BASHRC User Environment variablesSU user switches the user and loads the configuration file. bashrcSu-user switch User, load configuration file/etc/profile, load Bash_profileUser and user groups for changing filessudo chown [-r] Owner[:group] {file| Directory}For example: Also take jdk-7u21-linux-i586.tar.gz as an example. belongs

and paste H (move left one character ←), J (Next line ↓), K (Previous line ↑), L (move right one character →) User and User group management /ETC/PASSWD: Storing user accounts /etc/group: Storage Group account /etc/shadow: Store password for user account /etc/gshadow: Store password for user group account Useradd User Name Userdel User Name AddUser User Name Groupadd Group Name Groupdel Group Name passwd root: Set a password for root Su

Tags: color key font authentication dictionary keygen linux command LDAP user 36.1 Pwdhash: Password Hashishen generator 36.2 mkpasswd: Generate a new password applied to the user 36.3 Keytool: Key and certificate management tools 36.4 certutil: Certificate Server Administration Tool 36.5 vncpasswd: Create or change VNC login password 36.6 Ssh-keygen: Creating an SSH key 36.

-nand 11 use, tell read command to accept single word specifier exitCode 2-25[Email protected]:/data# cat Demo5 #!/bin/bashread-n1-p "Do you want to continue [y/n]" Answercase $answer in y|y) E Cho echo "fine,continue on ...";; N|n) echo echo "Ok,goodbye" exit;; Esacecho "This is the end of the script" [email protected]:/data#./demo5 does you want to continue [y/n]yfine,continue on]. . This is the end of the script　　Hidden mode read, the-S optio

belongs to Ubuntu, Debian Package management tool Yum belongs to Redhat, CentOS Package management tool Knowing these two points, there's no problem with using Hadoop or OpenStack. For more detailed reference: Generally known Linux systems are basically divided into two main categories: 12RedHat Series1 common installation package format RPM package, the command to install RPM package is "rpm-par

Tags: set action process dynamic display insert ifconf instruction switch directory tailIn the Linux learning process, we will use some common commands, the following summarizes some of our operations in the process of some common commands for everyone to use, mainly divided into: common directives, System management commands