crontab command

Today with the information collected through the online and their own practice, with the crontab command to do a remote server database backup, hope to be useful to everyone.The operation steps are as follows:1. Open Putty, enter the password here, and then go to:2. Create a path to save the backup file/mysqldata: After creating the file, you can see the Mysqldata folder in the root directory (and Var, usr

Background: The project needs to configure a scheduled task to scan the data table data, will be expiring orders marked out, write to the System message reminder table. Previously configured Crontab to execute PHP scripts directly, and then all the way to the process to achieve the end of the business. Recent projects have used the thinkphp framework, thinking that the framework for data manipulation encapsulation convenience, do not want to run the P

Firmware (CMOS/BIOS) post power-on self-check-à bootstrap loader (GRUB) (Load Kernel) à load Kernel (driver hardware) à START process init à read execution configuration file/etc/inittab Stage 1: BIOS startup 1. After pressing the power supply, execute-power-on self-check. Firmware-programs between software and hardware Detect cpu, memory, video card, keyboard, etc. Phase 2: GRUB boot guide phase 2. After self-check is passed, execute the self-lifting program GRUB load the kernel self-sta

#!/bin/bashIp= "' Ifconfig eth0|awk-f" [:]+ "' nr==2 {print $4} ' _$ (date%f%h%m)"Execution of the script through SH is normal, and the crontab scheduled task call is NULL,*/1 * * * */bin/sh/scripts/tar.sh >/dev/null 2>1Workaround:Solve the problem of changing the ifconfig in the script to the perfect path/sbin/ifconfigIp= "'/sbin/ifconfig eth0|awk-f" [:]+ "' nr==2 {print $4} ' _$ (date%f%h%m)"This article is from the "Zhongliang Linux Technology blog

Basic format:* * * * * commandTime-sharing Weekly commandThe 1th column represents minutes 1~59 per minute with * or */1The 2nd column represents the hour 1~23 (0 means 0 points)The 3rd column represents the date 1~31The 4th column represents the month 1~125th Column Identification Number Week 0~6 (0 = Sunday)6th List of commands to executeSome examples of crontab files:* * * * */usr/local/etc/rc.d/lighttpd restartThe example above represents a 21:30

Basic format:* * * * * commandTime-sharing Weekly commandThe 1th column represents minutes 1~59 per minute with * or */1The 2nd column represents the hour 1~23 (0 means 0 points)The 3rd column represents the date 1~31The 4th column represents the month 1~125th Column Identification Number Week 0~6 (0 = Sunday)6th List of commands to runSome examples of crontab files:* * * * */usr/local/etc/rc.d/lighttpd restartThe above example shows that 21:30 restar

character interface multi-user interface Ü Unsed custom Ü Xll graphical multi-user mode Ü Reboot restart Id: 5: initdefault # Runlevel view running level # Init [0123456Ss] run-level switch Stage 4: initialize sys V init Start process init ----- Read configuration file Grep command Grep-v '^ #'/etc/inittab | more Extract valid rows Inittab file analysis Id: run-levels: action "process Id: identifier, generally two digits or letters Run

writes date to time.log every 2 minutes (the following is an odd-minute execution)*/2 * * * * Date >> ~/time.log1-59/2 * * * * Date >> ~/time.log23:30 minutes a day to restart Apache * * * * /etc/init.d/apache2 restart23:30 points per month for the 1,10,20, restart Apache. 1,10,20 * */etc/init.d/apache2 restart23:30 restart Apache per month from 1 to 15th 1-15 * */etc/init.d/apache2 restartApache starts every 30 minutes from 23 o'clock to 6 in the morning. */30 23-7 * * */etc/init.d/apache

Restart TeamViewer every two hours to prevent the outside of the console execution: CRONTAB-E//Enter the Timer edit page, add the following command, Control+c!wq save 0 */2 * * * TeamViewer Deamon 0 */2 * * * echo "Have a break now." >>/tmp/test.txt separated by spaces or tabs between each domain. The format is as follows: minuteHour Day-of-monthMonth-of-year Day-of-weekCommands legal value 00-59 00-23 01-3

Crontab Scheduled Task configuration record, crontab task First, preface Today, simply record the configuration of the crontab Ii. Catalogue of Crontab /etc/crontab file This is the scheduled task for the system to run/var/spool/cron directory user-defined

Crontab for linux commands and crontab for linux commandsCron is a built-in service in Linux. Run the following commands to start, view, and disable the service. Service cron start // start service cron stop // close service cron restart // restart service cron reload // reload and configure service cron status // view service status The cron global configuration file is in the/etc directory: Cron. d/The sy

. Brilliant ~~Next I will try to summarize the basic usage of crontab, environment variables, and other issues to be aware. If you have any questions, you can leave a message to discuss them.----------------------------1. Basic crontab usageUsage: crontab [-u user] [-E |-L |-R]The crontab format is described as follows

Design of a scheduled task using crontab in CentOS The at command is for a task that only runs once and runs cyclically scheduled tasks. In linux, cron (crond) is the system service. The Linux system has a lot of planned work, so this system service is started by default. In addition, because you can also set scheduled tasks, Linux also provides the crontab

root run-parts/etc/cron.weekly 4 1 * * Root run-parts/etc/cron.monthly [Root@localhost ~]# The first four rows are the environment variables that are used to configure the Crond task to run, the shell variable specifies which shell the system will use, this is bash, and the second line of the path variable specifies the path to the System execution command. The third line of the mailto variable specifies that Crond's task execution information will b

Crontab: scheduled task execution. Crontab: scheduled task execution. I recently came into contact with the needs of scheduled execution programs, so I learned about crontab. This article first introduces the syntax knowledge of crontab, and then makes a demo. I. crontab syn