Cloud Applications

Php automatically generates thumbnails Based on URLs and handles high concurrency issues. The server generally has two types of thumbnails: 1. The advantage of generating a file during upload: the required thumbnails have been generated during the

In the DOS era, the command to list directories is dir and the command to clear the screen is cls. Similar commands in Linux are ls and clear. if you are not used to them, you can use the same command as an alias: [blackrose @ localhost ~]. $

View the parameters of some common services during compilation and installation: 1. Nginx compilation and installation parameters [root @ test ~] #/Usr/local/nginx/sbin/nginx-Vnginxversion: nginx/0.7.65builtbygcc4.1.220080704 (RedHat4.1.2-48)

Many software applications need to bind MAC addresses (for example, OpenCountry). sometimes we need to modify the MAC address of the NIC for special purposes. 1. Method 1: Use the command to temporarily modify: ifconfigeth0downifconfigeth0hwetherxx:

In Dos/Windows, rename the file. The book says that the mv should be used for renaming files or directories in Linux. I have been doing this all the time, but ignored that there is also a command named rename in Linux. All are rename, but the

It is essential to use the command line in linux. Mastering the shortcut keys can help you get twice the result with half the effort. The most commonly used key should belong to the Tab key, and the function is automatically completed. It is mainly

In centos, you can use yum to conveniently and quickly install the required software and libraries. if The yum source is not good, the installation speed will be very slow. by default, centos official sources appear to be outside China, so the speed

When the system slows down, we may first focus on the cpu metrics. sometimes we find that the cpu usage is not high at all, but the system is still stuck, in this case, you may need to worry about other things that affect performance? Disk I/O

Common Linux operating system logon files include: 1)/var/log/secure: file used to log on to the system to access data, such as pop3, ssh, telnet, ftp and so on will be recorded here. 2)/ar/log/wtmp: record the login information record, encoded, so

This section describes how to automatically start SVN when Linux is started. in the previous section, we will explain how to automatically start the SVN service when Windows is started. through this section, you can make a comparison, let's take a

Mkisofs (makeisofilesystem) function description: creates an ISO9660 image file. Syntax: mkisofs [-adDfhJlLNrRTvz] [-print-size] [-quiet] [-A & lt; application ID & gt;] [-abstract & lt; summary File & gt;] [-B & lt; boot image file & gt;] [-biblio]

When you remotely log on to linux using telnet or SSH, if the connection is interrupted abnormally, the system opens a new session and cannot restore the original session. The screen command can solve this problem. The Screen tool is a terminal

In actual work, the company does not directly give the root user to the employee, but temporarily obtains the root permission of the system through the employee's own account. 1. my current test environment is: redhatlinux6 [root @ rhel1xcg] # uname-

The locate command allows you to quickly search for specified files in the file system. The method is to first create an index database that includes all file names and paths in the system, and then query the index database when searching, instead

It is actually a few simple commands. (1) after the USB flash disk is mounted and deleted and inserted into it, the command line will display and respond. In this case, use $ fdisk-l to view all the partitions and drive letters, and then $ mkdir/mnt/

Set the root user to telnet to the linux system. by default, the ROOT user cannot connect to the Linux operating system through telnet, which is also insecure. but technically, it can be implemented. # mv/etc/securetty. save and exit the bak. You

A chance of accidentally installing a DB database found that the installation was slow, so the system engineer suggested that I test the hard disk read/write speed and found that the read/write speed was only about 200, the machine is dellR710

I. LVM (LogicalVolumeManager) is a mechanism for managing disk partitions in Linux. LVM is a logical layer built on hard disks and partitions, to improve the flexibility of disk partition management. DM logical device introduction 1. physical volume

These commands are very useful, but the usage is not too high. you can collect them for future reference. Reprinted connection: http://my.oschina.net/hunterli/blog/140783 System # Uname-a # View kernel/OS/CPU information # head-n 1/etc/issue # View

The tftp server configuration is in redhatlinux5. for detailed steps, see Redhat 1. enter the root permission under the terminal. first check whether the tftp server and client components are installed. verify the command: rpm-qa | grep tftp (see