When loading CentOS-7.0-1406, there are many optional versions. For ordinary users, they don’t know which one to choose. Here is a brief introduction: (1) CentOS-xxxx-LiveCD.ios and CentOS-xxxx- What is the difference between bin-DVD.iso? The former only has 700M, and the latter has 3.8G. The difference is not only in size, but the more essential difference is that CentOS-xxxx-LiveCD.ios can only be loaded into the memory and run, and cannot be installed. Only CentOS-xxx-bin-DVD1.iso can be installed on the hard disk. (2) CentOS-xxx-bin-DVD1.iso, Ce

Open the centos7 page and appear: welcome to emergency mode! afterloggingin, type "journalctl -xb" to viewsystemlogs, "systemctlreboot" toreboot, "systemctldefault" to tryagaintobootintodefaultmode. giverootpasswordformaintenance(??Control-D???): Solution: execute r

There is a lot of garbage in the tmp directory in the centos7 system. If you want to clear the garbage, how should you do it? Let’s take a look at the detailed tutorial below. To view the list of files in the tmp file directory, execute the command cdtmp/ to switch to the current file directory of tmp, and execute the ll command to view the list of files in the current directory. As shown below. Use the rm command to delete files. It should be noted that the rm command deletes files from the system forever. Therefore, it is recommended that when using the rm command, it is best to give a prompt before deleting the file. Use the command rm-i file name, wait for the user to confirm deletion (y) or skip deletion (n), and the system will perform corresponding operations. As shown below.

Set password rules for security reasons Set the number of days after which passwords expire. User must change password within days. This setting only affects created users, not existing users. If setting to an existing user, run the command "chage -M (days) (user)". PASS_MAX_DAYS60#Password expiration time PASS_MIN_DAYS3#Initial password change time PASS_MIN_LEN8#Minimum password length PASS_WARN_AGE7#Password expiration prompt time Repeat password restriction use [root@linuxprobe~]#vi/etc/pam.d/system-auth#nearline15:

To extend PHP function functionality, you can use extensions and third-party modules. Extensions provide additional functions and classes that can be installed and enabled through the pecl package manager. Third-party modules provide specific functionality and can be installed through the Composer package manager. Practical examples include using extensions to parse complex JSON data and using modules to validate data.

1. The compressed folder is a zip file [root@cgls]#zip-rmydata.zipmydata2. Unzip mydata.zip into the mydatabak directory [root@cgls]#unzipmydata.zip-dmydatabak3.mydata01 folder and mydata02.txt are compressed into mydata.zip[root@cgls]#zipmydata.zipmydata01mydata02.txt4. Decompress the mydata.zip file directly [root@cgls]#unzipmydata.zip5. View myd

1.UncaughtError:Calltoundefinedfunctionmb_strlen(); When the above error occurs, it means that we have not installed the mbstring extension; 2. Enter the PHP installation directory cd/temp001/php-7.1.0/ext/mbstring 3. Start phpize(/usr/local/bin /phpize or /usr/local/php7-abel001/bin/phpize) command to install php extension 4../configure--with-php-config=/usr/local/php7-abel

centos7 uses the ipv6 protocol. If a problem occurs, it will be difficult to troubleshoot. So if you want to turn off ipv6, how should you turn it off? Let’s take a look at the detailed tutorial below. 1. Use the ifconfig command to check the network card information. If inet6fe80::20c:29ff:fed0:3514 appears, it means that the machine has ipv62 enabled. Edit the /etc/sysctl.conf configuration and add net.ipv6.conf.all.disable_ipv6=13. Edit /etc/sysconfig/network configuration, add NETWORKING_IPV6=no, save and exit 4. Edit /etc/s