Linux

SignalSignals are asynchronous interprocess communication modesHow the process responds to the signal: IgnoreSIGKILL and SIGSTOP cannot be ignored captureWhen the process receives a signal, the signal processing function executed at this time

                 Scheduled Task management                  At  One-time task settings.   Service Script:/etc/init.d/atd  use method;   #at   13:00  2017-11-4  Enter At> interface, Set up tasks.   finally press Ctrl+d to submit the key combination.

User CategorySuper User: Uid range 0 Root User: uid=0 (root) gid=0 (root) groups=0 (root) Normal User: Created by Administrator, UID Range (500-65535)-- EG:OMC User: uid=502 ( OMC) gid=502 (OMC) groups=502 (OMC) intended users: to meet the needs

monitoring Linux Server memoryInternational practice, we need to know what is the server's memory, what is the function of memory. This is not too much to introduce, Linux performance monitoring requires us to have a certain understanding of the

1. Install the client software using XL2TPD,PPPYum Install-y xl2tpd PPP2. Configure XL2TPDVim/etc/xl2tpd/xl2tpd.confAppend the following code at the bottom[Lac Gomez]Name = AomengLNS = www.gomezddup.comPppoptfile =/etc/ppp/peers/gomez.l2tpdPPP debug

View Status:Iptables-l-NAdd the following methods for opening a specific port:Use Iptables to open the following ports/sbin/iptables-i input-p TCP--dport 8000-j ACCEPTSave/etc/rc.d/init.d/iptables SaveRestart ServiceService Iptables RestartSee if

Kernel informationCat/proc/version[Email protected]172- to- the-157: ~/wslink$Cat/proc/Versionlinux version4.4.0-1061-aws ([email protected]024) (GCCVersion5.4.0 20160609(Ubuntu5.4.0-6ubuntu1~16.04.9) ) # --ubuntu SMP Fri May - +: -:

1. Permissions 1.1 View PermissionsYou can see the details of a file by using the Ls-l commandHere is a message explaining the role of each position character-rwxr--r--. 1 root root 32 June 10:15 choose.sh(1) 0-9-bit description: No. 0

I. Stat, FSTAT, Fstatat, Lstat functionsThe prototype of the function is:#include intStatConst Char*restrict Pathname,structStat *restrict buf);intFstat (intFdstructStat *buf);intLstatConst Char*restrict Pathname,structStat *restrict buf);intFstatat

Https://www.cnblogs.com/liaocheng/p/4243589.htmlLinux Yum Command detailedYum (full name Yellow dog Updater, Modified) is a shell front-end package manager in Fedora and Redhat and SuSE. Based on RPM package management, the ability to automatically

First, Lseek functionEach open file has a "current file offset" associated with it. It is usually a non-negative integer used to measure from the beginning of the fileThe number of bytes computed. Typically, read and write operations start at the

Searching for files or folders is a common requirement. We can use a variety of commands to achieve our needs.Find Command Implementation SearchfindIt's English, look for the meaning. This command can be very helpful in searching for what we

Build LVS Load Balancer Pre-set on Linux,centos7 Prepare five virtual machines Four sets of Centos7 One to do scheduling one to do NFS cache Two do Wed clusters One windows7 begins to be configured individually

Linux chmod CommandsChmod is used to change the access rights of a file or directory. Users use it to control access to files or directories. There are two ways to use this command. One is to includeThe text setting method of the letter and operator

4.5 disk formatting (top)Linux default partition system, CENTOS6 previously used ext file system, CENTOS7 is XFS file system, use mount to view/dev/file system typeFile system format, file system format can be ext3, ext4 or XFS type, an empty file

Expect is a software tool for automated control and testing in UNIX systems, made by Don Libes, as an extension of the TCL scripting language, applied in interactive software such as TELNET,FTP,PASSWD,FSCK,RLOGIN,TIP,SSH, etc.Yum Install-y

First, the problem appearance:Program Log error: Java.io.IOException:Too many open files atSecond, the solution:1. Check the maximum number of files that the system is allowed to open:Cat/proc/sys/fs/file-max2. View the maximum number of files

System Detection Tool top command in LinuxThis article transferred from: https://www.cnblogs.com/zhoug2020/p/6336453.htmlFirst, describe the meanings of some of the fields in top:Virt:virtual Memory usage Virtual RAM1. The process "required" virtual

Cluster (Cluster): Multiple computers, in order to solve a set of problems, usually to improve the performance of the system;Clusters are divided into: Load Balancing cluster (LB), High availability cluster (HA), High performance cluster (HP);One,

Preface 1.   What is regulator?     regulator translated as "regulator", is divided into voltage regulator (voltage regulator) and current regulator. The General power management chip (Power Management IC) contains one or more regulator.  2. What is