Linux

The read command is used to read text from the keyboard or standard input. Reads input from the user interactively. The default is to use "enter" as the end. Typically used in an automated SH script. #用不回显 (non-echoed) way to read the password $

When you have more than one server, if a single login to manage that can not say the trouble, so the batch management tool came into being. As long as you set up SSH no password login: SSH-KEYGEN-T RSA Ssh-copy-id User@host A password-free SSH

The data transfer for the Linux command execution process is as follows: 1 standard input (stdin): code 0, using 2 standard output (STDOUT): Code 1, using > or >>; 3 standard error Output (STDERR): Code 2, using 2> or 2>>; where > indicates

The Linux Pipeline command is ' | ', which enables continuous processing of the data, with the following schematic diagram: Attention: 1 pipe command only for processing standard output (that is, correct output), for standard error output, will

Disk Partitions-fdisk Fdisk commands do not need to be remembered, because after you enter M, you will see detailed help information, as follows: [Root@lx15/data]# FDISK/DEV/SDA The number of cylinders for this disk was set to 36404. There is no

When the user logs on, the following two profiles will be read: 1)/etc/profile: System global configuration file, it is best not to modify the file 2 ~/.bash_profile or ~/.bash_login or ~/.profile: User-Private configuration file Global

Framebuffer the corresponding source file is in the linux/drivers/video/directory. The total abstract device file is fbcon.c, and there are source files associated with various graphics drivers in this directory. (i), Analysis framebuffer Equipment

Overview of Shared memory The shared memory area is the fastest form of IPC, where data delivery is no longer related to the kernel, in other words, processes no longer pass data to each other by executing system calls into the kernel. That is,

Linux rescue mode is widely used when Linux encounters some configuration files, such as kernel problem/fstab, and disk fsck error and so on when the system cannot start. This eliminates the complex and time-consuming task of reloading our systems

RAID English full name redundant array of independent disks meaning "Independent disk redundancy", referred to as the disk array. RAID0 is used to extend the disk, the disadvantage if a hard drive breaks down the system crashes; RAID1 is one to do

Modify/delete garbled file name I do not know if you have encountered such a file, because it is garbled, files can not be deleted, then we can consider using the following command to delete files or directories Ls-i//List file nodes Find./-inum

You may have a good understanding of the load mean of Linux (load averages). The load mean can be seen in the uptime or top commands, and they may appear this way: Load average:0.09, 0.05, 0.01 A lot of people understand that. Load mean: Three

iSCSI Service-Side IP192.168.254.172 Client 1 192.168.254.46 Client 2 192.168.254.158 Service-side configuration 1, the service side installs the Scsi-target-utils [Root@localhost ~]# Yum Install scsi-target-utils-y 2, if there is a separate

1.sudo Introduction Sudo is a common tool that allows ordinary users to use Superuser privileges under Linux, allowing the system administrator to allow ordinary users to perform some or all of the root commands, such as HALT,REBOOT,SU, and so on.

Information for the file to be set: v0id6@v0id6-eof ~ $ ls Testacl-la -rw-rw-r--+ 1 v0id6 v0id6 9 March 2 14:21 testacl Gets the access control list for the file (this is the value before the SETFACL setting is used) v0id6@v0id6-eof ~ $ getfacl

Yum is the abbreviation of Yellowdog Updater modified. Yum's idea is to use a central warehouse (repository) to manage some or even a distribution application, and to perform related upgrades, installations, deletions, etc. based on the calculated

First, regular expressions In computer science, regular expressions are used to describe or match a series of strings that conform to a certain syntactic rule; in a text editor or some tool (such as bash environment), regular expressions are often

First, Memory usage instructions The free command provides a more concise view of system memory usage relative to top: [Root@rac1 ~]# Free Total used free shared buffers Cached mem:1035108 1008984 26124 0 124212 413000 -/+ buffers/cache:471772 5

In Linux often found that there is little free memory, it seems that all the memory is occupied by the system, the surface is not enough memory, it is not. This is an excellent feature of Linux memory management, and in this context differs from the

Today a server root user can not log in, the normal user may log in. Normal user su to root user also error Su:bash:No such file or directory View the next passwd file oracle@linux-35:~> Cat/etc/passwd|grep Root Root:x:0:0:root:/root:cd The