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Article directory Operating environment and relevant instructions Operating environment Related instructions Firewall related instructions Port number related instructions Gitlab related instructions File transfer Backup and restore backups Gitlab related configuration information reduction Visi ...

1: Realization mechanism The implementation idea of Linux linked list is to create only one next pointer in the node, and use the pointer to connect each node for printing and searching, and then perform type conversion. The circular list is changed on the basis of the Linux list. The next of the las ...

python introduction Supported systems: cross platform Advantages: high development efficiency Disadvantages: slow execution Application: website development, automatic operation and maintenance, game development, crawler, data analysis, artificial intelligence Alibaba cloud and Tencent cloud View python version [root@Tencent ~]# python Pyth ...

Identification standard First of all, we need to know what kind of identity is 32-bit and 64 bit. PC server X86 series I386--I686 are all 32 bits X86 ʄ is 64 bit Order is not too much, in order to prevent the obstacles of selectivity, choose the first method unanimously, the latter is only for supplement. Method 1: [roo ...

According to the standard documents of SM3 hash algorithm, it is easy to write the C language implementation of its message extension function: #include <stdint.h> void expand_data(uint32_t W[68], uint32_t data[16]) { uint32_t j, P1, X; for(j = 0; j < 16; j++) W[j] = data[j]; for(j = 16; j < 68; j++) { X = W[j-16] ...

It is very convenient for Red Hat Enterprise Linux and CentOS Linux to use YUM installation software. After installing CentOS operating system, if you can use the domestic software warehouse, the speed will be faster. Therefore, we need to modify the configuration file of the YUM source. The suffix of these configuration files is. repo, which i ...

Greenplum has iterated several small versions at present in version 6. With the update of the version, bug s are constantly fixed. Friends who are going to try it can start. As the first post of the first working day of the new year, it must start from the "groundbreaking" 6.0. The following content is relatively simple, suitable for ...

Experiment Description: In many automation tasks, scripts often get information by reading configuration files. After the upgrade of red hat system (CentOS7/RHEL7), the naming method of "consistent network device interface" is adopted for network card naming, resulting in different network card names of different devices. In order to ...

Online upgrade from CentOS6-x to CentOS7-x   origin Compared with the Debian Linux distribution (such as Debian and Ubuntu), they can support online large version upgrade very well. The large version upgrade of Red Hat Linux distribution (such as red hat and CentOS) has always been a problem criticized by people. This situa ...

Summary We know that relational database tables are better suited for flat lists than for hierarchical data with parent-child relationships that can be directly managed like XML. First, define the hierarchy we are discussing, which is a set of data where each entry can have only one parent and zero or more children (the only exception is the ...