One of the Linux (CentOs6.6) System Learning Notes Series

Because all of the new company's applications are deployed to the Linux server, and then the boss asked us every yard must understand a bit of Linux system knowledge, and has never been exposed to the Linux system, but do not want to lag behind others, So this time on the crazy of the evil to fill a bit of knowledge of Linux, mainly to watch the network above some of the video tutorial, and then the video operation of their own, probably familiar with a bit, today is the fourth day, and then summed up a bit, here are some of the main record some of these days of learning notes, Hope to witness the growth of their own ... I also hope to help some friends.

Environment:
Physical machine Operating system: Widows7 64bit
Virtual machines: VMware WorkStation10.0
Linux operating system: CentOS6.6

About the installation process, Baidu has a lot of great gods have written a good tutorial, but also very detailed, direct search and follow the operation can be ...

--------------------------------------------------------------------------------------------------------Day1linux Learning: Mount: Must partition 1,/(root partition) 2, swap partition (swap partition, memory twice times (in case of real machine memory not exceeding 4GB), not more than 2GB) recommended partition 1,/boot (boot partition, 200MB) file system structure: root directory-- /--"/dev/sda3 -- /boot--"/dev/sda1 --/ etc --passwd--Shadow--Group-- /home--"/dev/sda2 In Linnux, the/home directory is used as a drive letter, also known as a mount point----------command prompt [[email protected] ~] #其中: root: Currently logged on user localhost: host name    ~  Current directory (home directory) user's initial logon location user's home # Superuser's prompt is the command format command [options] [parameters] ([] brackets are optional) Note: Individual commands are used without following this format when there are multiple options, you can Write together simplify options with full options-a equals--all .-----LS1, query the contents of the directory: Lsls [options] [file or directory] options:-a displays all files, including hidden files-L Show Detailed information-d View Directory Properties-h User-friendly display file size-I show InodeThere are 7 types of files in Linux: Three commonly used: the first letter to differentiate-represents a normal fileD indicates that the directory L represents a soft link file and special files do not require ordinary users to do what operation block device files, character device files, socket files, pipe file user groups and permissions:-rw-r--r--1.-File type (-Indicates normal file D means directory L means soft link file) 2, rw-r--r--u owner G belongs to group O Others 3, R read W write x execute 4,-rw-r-  -R--. The last one "." Represents ACL permissions 5,-rw-r--r--. 1 root 1272 Mar 06:30 Anaconda-ks.cfg1 represents the reference count, which indicates that the first root is referenced once (the owner of the current file) the second root is the owning group (the group to which the current file belongs)-h User-friendly display file size-d View Directory PropertiesLs-l/etc/View the properties of all the files in the/etc/directory ls-ld/etc/View the property information of the/etc/directory itself LS-LH install.log (install.log = parameter) 6, Linux with "." The file at the beginning represents the hidden file 7, ls-i view the file ID number (I node) each file will have an ID number system is based on this ID number (I node) to find the file, determine where the file is located------------------------------------------------------------------------------------------------------------ ------Day21, Directory Processing command: Build directory: mkdirmkdir-p [directory name]-p Recursive creationCommand English original: Make directories2, switch directory: CDCD [directory] English original: Change Directory simplified operation: cd ~ Enter the current user's home directory CD into the current user's home directory CD-go to the last directory CD. Go to the top level directory CD. Go to current directory PWD view current directory Ctrl + L shortcut Clear screen CD japan/cd/root/root relative path and absolute path relative path: Refer to the current directory, and look for such as: [[email protected] ~]# CD. /user/local/src/absolute path: Starting from the root directory, first-level recursive lookup. In any directory, you can enter the specified location such as: [[email protected] ~]# CD/ETC/CDCD. /ROOT/JAPAN/CANGLS/CD. /root/japan/cangls/identify the directory when you press the TAB key to identify the command when you press the TAB key to identify the command completion and directory completion 3, the directory location: pwdpwd (print working directory) 4, delete empty Catalog: Rmdirrmdir [directory name]--Remove empty directoriesRmDir bols/rmdir JAPAN/5, deleting files or directories: RMRM-RF [files or directories] Remove option:-r Delete Directory (remove)-F Mandatory (Force)In Linux, the root user is the real Super Administrator with the highest privileges RM-RF/RM-RF/This command will remove all files from the root directory, but the system will not crash rm-rf/tmp/* or rm-rf/tmp/need to note 6, copy command: C PCP [Options] [Original file or directory] [target directory] Copy option:-r Copy Directory-p Joint file attribute copy-D If the source file is a linked file, copy the link property-A is equivalent to-PDRCp-r japan//TMP/CP in the copy directory before the need to add-rll/tmp/ls/tmp/ll command = LS-L7, cut or rename command: MVMV [source file or directory] [target directory] MOVEMV japan//TM P/JAPAN1MV do not need to add the-r option when cutting the MV is the Cut command (the source file and the target file is under different directory) is also renamed the command (the source file and the target file under the same directory)---------------------------------------------------------------------The role of DAY31 and common directories/root directory/bin command to save directories (commands that ordinary users can read)/boot directory to start related files/ Dev Device file save directory/ etc configuration File save Directoryhome directory for normal users/lib System Library Save directory/mnt System mount directory (empty directory)/misc mount Directory (empty directory)/media mount Directory (empty directory)/root home directory for super users/ tmp temp directory/sbin command to save directory (a directory that can be used by super users)/proc write directly to memory/sys write directly to memory/ USR system software Resources Directory/usr/bin/System command (normal user)/usr/sbin/system command (super User)/ var system related document contentThe /proc and/sys directories cannot be directly manipulated, and both directories hold the memory overload pointIs the memory of the drive letter, these two directories of data is directly written into memory, so these two directories do not allow direct operation Lsls usr/root directory of the bin and sbin, the USR directory of bin and Sbin, these four directories are used to save system commands. Where the file in the bin directory can be executed by ordinary users (either the root directory or the USR directory) and the files in the Sbin directory can only be performed by the root superuser, either home directory root (superuser root) or home (normal user), and the TMP directory to put content freely Do Exercise 2, how Linux shuts down 1, direct power off 2, init 0 3, Telinit 0 4, Shutdown-h now 5, HALT6, poweroffshutdown-h now shutdown

One of the Linux (CentOs6.6) System Learning Notes Series