• Method of setting firewall for server of Linux system


    Firewalls help filter access ports and block login attempts using brute force. I prefer to use CSF (config server firewall), a powerful firewall. It uses iptables, which is easy to manage, and provides a web interface for users who are not good at entering commands. To install CSF, log in to the server and switch […]

  • A simple way to view and turn off Linux system services


    The essence of server is to provide access functions for various services. Make the server run only the required services and close the unused services. This will not only free up some system resources, but also make the server more secure. For example, if you just run a simple server, you obviously don’t need an […]

  • Method of configuring SNMP on Linux system


    Configuring SNMP on Debian or Ubuntu To install SNMP agent (snmpd) on Debian based systems, run the following command:     Copy code The code is as follows: <a></a>[email protected]:~# apt-get install snmpd    Then, edit the configuration file as follows.     Copy code The code is as follows: <a></a> [email protected] :~# vim /etc/snmp/snmpd.conf</p> agentAddress udp:161#Define a […]

  • How do Linux systems switch users with commands?


    Beginner Linux, record a simple operation 1. I installed a virtual machine. First, open the virtual machine 2. Right click on the desktop and select open terminal 3. Enter the command to see the current user 4. Enter the command Su – root and password to switch to administrator 5. You can switch to full […]

  • Solution to the accidental deletion of Yum management tool in Linux


    Today, when I was installing the program, I found that a plug-in was not installed, so I clicked a command without looking Copy code The code is as follows: yum remove yum And then there’s a cup Copy code The code is as follows: [[email protected] ~]# yum -bash: /usr/bin/yum: No such file or directory   […]

  • Backup parts encrypted with luks on Linux


    For security reasons, some of us encrypt hard disk drives at home or on VPS through Linux unified key configuration (luks), and the capacity of these drives will soon grow to tens or hundreds of GB. Therefore, although we enjoy the security brought by luks devices, it’s time to start considering a possible remote backup […]

  • Use the xkill command to kill unresponsive processes in Linux systems


    How do we kill a resource / process in Linux? Obviously, we’ll find the PID of the resource and use the kill command. To be more clear, we can find the PID of a resource (such as terminal):     Copy code The code is as follows: $ ps -A | grep -i terminal 6228 ? […]

  • Method of IP forwarding on Linux system


    Hello, everyone. Today, let’s learn how to use iptables to realize IP forwarding (packet forwarding) from one network interface to another on Linux. The concept of IP forwarding is to make Linux machines send data from one network to another like routers. Therefore, it can be used as a router or proxy server to share […]

  • Three implementation methods of virtual host under Linux 7


    1、 Same IP address, different port numbers Virtual host 1: the host IP address is, the port number is 80 (the default port), and the DocumentRoot is / var / www / vhost1. Create the virtual host site home page file in the DocumentRoot directory. [[email protected] ~]# cd /var/www/ [[email protected] www]# mkdir vhost1 [[email protected] […]

  • Summary of common network commands under Linux


    You can use any of the following commands:Nstat command: network statistics tool Type the following command:     Copy code The code is as follows: # nstat Output example:     #kernel    IpInReceives                    133243             0.0    IpInDelivers                    133243             0.0    IpOutRequests                   92904              0.0    IcmpOutErrors                   97                 0.0    IcmpOutTimeExcds                97                 0.0    IcmpMsgOutType3                 97                 0.0    TcpActiveOpens                  538                0.0    TcpEstabResets                  56                 0.0    TcpInSegs                       […]

  • Using iptraf for network monitoring in Linux system


    iptrafIt is an IP LAN monitoring tool developed based on ncurses. It can generate various network statistics, including TCP information, UDP statistics, ICMP and OSPF information, Ethernet load information, node statistics, IP checksum errors and other information. Its ncurses based user interface will also save users from the nightmare of command-line options.function     An IP […]

  • Solution to the error CP: organizing directory in copying directory in Linux


    When copying a directory to another directory in a Linux system, an error will appear when using the CP command 1. Under the / home / directory, create a new directory, for example: 123 2. Copy directory 123 to the / TMP / directory and use the CP command 3. System error,cp:omitting directory ‘123’  4. […]