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  • Solve the problem that virtualbox cannot open the virtual machine and the solution that Linux cannot access virtualbox
    Solve the problem that virtualbox cannot open the virtual machine and the solution that Linux cannot access virtualbox
    I installed a virtual machine on a deepinlinux physical machine with the help of virtualbox, but the virtual machine cannot be directly accessed on the physical machine (deepinlinux system). What should I do? Let’s take a look at the solution to this problem. The IP address of the virtual machine is 10.0.2.15, as shown in the figure below. On the physical machine (deepinlinux system), the direct ssh connection cannot be accessed normally (the openssh-server service has been installed), and it keeps getting stuck without any response. To solve the above problem, first run virtualbox, click "Management" and select "Global Settings". pop-up
    LINUX . ssh 1163 2024-01-06 15:28:11
  • In-depth analysis of the systemd management system under CentOS 7
    In-depth analysis of the systemd management system under CentOS 7
    CentOS system startup process: POST-->BootSequence-->Bootloader-->kernel+initramfs(initrd)-->rootfs-->/sbin/initinnit program: CentOS5: SysVinitCetnOS6:UpstartCentOS7:SystemdSystemd new features: system SysVinit and LSBinitscripts Implement parallel startup of services when compatible system boots; use socket/D-Busactivation and other technologies to start services; in order to reduce system startup
    LINUX . ssh 689 2024-01-06 08:53:42
  • Use Ansible to automate the deployment of serverless applications
    Use Ansible to automate the deployment of serverless applications
    Introduction Ansible is designed to be the simplest deployment tool for practical work. This means it is not a complete programming language. You need to write a YAML template that defines the tasks and lists any tasks that need to be automated. Most people think of Ansible as a more powerful "SSH in a for loop", and in simple use cases this is true. But in fact, Ansible is a task, not SSH. In many cases we connect via SSH, but it also supports Windows Remote Management (WinRM) on Windows machines, and things like HTTPS API as a common language for cloud services. In the cloud, Ansible can operate on two independent levels
    LINUX . ssh 935 2024-01-05 23:44:43
  • How to remotely verify SSH service configuration and policy through ssh_scan
    How to remotely verify SSH service configuration and policy through ssh_scan
    Introduction ssh_scan is an easy-to-use SSH service parameter configuration and policy scanner program for Linux and UNIX servers. Its ideas come from the Mozilla OpenSSH Security Guide. This guide provides a reliable security policy baseline recommendation for SSH service parameter configuration, such as Encryption algorithms (Ciphers), message authentication information code algorithms (MAC), key exchange algorithms (KexAlgos) and others. ssh_scan has the following benefits: its dependencies are minimized. ssh_scan only introduces local Ruby and BinData to perform its work, without too many dependencies. It is portable, you can use ssh_scan in other projects
    LINUX . ssh 631 2024-01-05 23:12:15
  • How to change Ubuntu's apt-get update source?
    How to change Ubuntu's apt-get update source?
    Manually modify Ubuntu's apt-get source 1. Use the ssh tool to connect to Ubuntu (I use xshell) 2. Type cd/etc/apt/3 on the command line and back up the source.list file in this directory (you must have sudo permissions) ), then there is a source.list.bak file. 4. Clear the source.list file content (note: it cannot be restored after clearing, so you need to perform the previous step to back up the file in advance). At this time, use sudo to prompt that the permissions are insufficient. Switch directly to the root user and execute this command. 5. Use vim to open source.list, press the i key to enter the editing mode, paste the source address to be modified, and then press
    LINUX . ssh 967 2024-01-05 15:40:27
  • Steps to install Greenplum 4.3.5.2 on CentOS 6.6
    Steps to install Greenplum 4.3.5.2 on CentOS 6.6
    On the GP official website, I can't see the corresponding version of the latest GP on Centos, so just use the RedHat version. Foreword: The installation of GP is roughly as follows. Select one host as the Master machine and the others as Segment machines. Since there are not that many machines, I opened three centos6.6 virtual machines in 1+2 mode. When installing, remember that GP can be installed on the Master machine first, and then you can perform similar remote installations by establishing mutual trust (gpssh-exkeys) between the Master machine and the Segment machine. You can log in to all machines through gpssh and perform what you want. This includes creating a user, copying the installed GP, and a series of other operations. Of course, in An
    LINUX . ssh 1266 2024-01-04 21:48:37
  • Introducing automatic logout methods on Linux to prevent long periods of user inactivity
    Introducing automatic logout methods on Linux to prevent long periods of user inactivity
    Let's imagine this scenario. You have a server that is frequently accessed by many users from various systems on the network. It is possible that some users forget to log out of the session leaving the session open. We all know how dangerous it is to leave a user session connected. Some users may use this to intentionally do things that damage the system. And you, as a system administrator, will you go to every system to check whether the user has logged out? In fact, this is completely unnecessary. And if there are hundreds or thousands of machines in the network, this is too time-consuming. However, you can have users automatically log out if they are inactive on the machine or SSH session for a certain period of time. This tutorial will teach you how to do this on a Unix-like system. not at all
    LINUX . ssh 1390 2024-01-04 16:38:16
  • How to change the host name in Ubuntu 15.04? Ubuntu, how to change the host name in 15.04
    How to change the host name in Ubuntu 15.04? Ubuntu, how to change the host name in 15.04
    1. Temporary modification; root@ubuntu15:/#hostnameXXXX so that the host name is temporarily modified to XXXX, but the effective host name will not be immediately displayed in the terminal. Re-open a terminal window (the terminal connected through ssh needs to be reconnected) Yes), in this way, the new host name is not saved in the system, and the host name will be restored to the original host name after the system is restarted. 2. Permanent modification: Directly edit the content of /etc/hostname as follows: XXXX The host name is changed to XXXX after restarting, and it remains unchanged after restarting. How to modify the host name on CentOS or RHEL7: https://www.jb51.net/os/RedHat/
    LINUX . ssh 764 2024-01-04 11:22:43
  • Teach you how to execute Java jar package in Linux system
    Teach you how to execute Java jar package in Linux system
    Introduction to the method of running jar packages under Linux. When you need to use a Java program developed on Windows to run on Linux, you need to package the Java program into a jar package and upload it to Linux for running. The following content will introduce several A method to start jar packages in the background under Linux. Optimization method one: java-jarxxx.jar&& means running in the background, the ssh window is not locked, but when the window is closed, the program will still exit Optimization method two: nohupjava-jarxxx.jar&nohup means running the command line without hanging up, when the account exits or is closed Terminal, program still runs when executing job with nohup command
    LINUX . ssh 1645 2024-01-04 10:24:21
  • 20 essential commands for system administrators
    20 essential commands for system administrators
    Introduction In this booming environment of new tools and diverse development environments, it is necessary for any developer and engineer to learn some basic system management commands. Specific commands and toolkits help developers organize, troubleshoot, and optimize their applications, while also providing operators and system administrators with valuable triage information when errors occur. Whether you are a novice developer or looking to manage your own applications, the following 20 basic system administration commands can help you better understand your applications. They can also help troubleshoot system failures such as why an application works locally but not on a remote host. These commands apply to Linux development environments, containers, and virtual machines. 1.curlc
    LINUX . ssh 1482 2024-01-04 09:05:59
  • Configuration tutorial for implementing SSH one-way passwordless access on CentOS
    Configuration tutorial for implementing SSH one-way passwordless access on CentOS
    Recently, I have been researching a file system that requires remote installation of software on the client computer and access without an SSH password. In addition, it is necessary to remotely transfer files to the client computer. It is inconvenient to enter the root password every time, so I thought of using sshkey to generate the public key and private key. key to verify without having to enter the root password every time. Server architecture: System: CentOS6.5x64 Control terminal A: 192.168.0.150 Remote host B: 192.168.0.151 Principle: Use sshkey to generate public key and private key. The key is equivalent to a key, and the public key is equivalent to a When locking a door, of course we hold the key to unlock it. In the same way, we put the key on the local server, which is server A, and put the public key on the remote server.
    LINUX . ssh 1072 2024-01-04 08:16:41
  • Git Series (2): Getting Started Guide to Git
    Git Series (2): Getting Started Guide to Git
    Introduction Because Git is so popular, if you can at least be familiar with some basic Git knowledge, it will bring a lot of convenience to your life. If you can master the basics of Git (you can, I swear!), then you'll be able to download anything you need and maybe even make some contributions in return. After all, that's the essence of open source: you have access to the code of the software you use, the freedom to share it with others, and the right to modify it if you wish. Once you're familiar with Git, it makes all of this easy. Reading and Writing Generally speaking, there are two ways to interact with a Git repository: you can read from the repository, or you can write to the repository. It's like a file: sometimes you open a
    LINUX . ssh 1299 2024-01-03 19:05:03
  • How to terminate unused or idle SSH sessions
    How to terminate unused or idle SSH sessions
    Introduction How to close an inactive ssh session? First use the w command to identify the inactive or idle ssh session, then use the pstree command to obtain the PID of the idle session, and finally use the kill command to close the session. Let's assume that when you are working on a server via ssh, your session connection is disconnected due to network, power, or local PC restart. You may or may not log into the server again to continue working, but you will always be left with the ssh session that was not closed before. How to close an inactive ssh session? First use the w command to identify the inactive or idle ssh session, and then use the pstree command to obtain the PID of the idle session.
    LINUX . ssh 1226 2024-01-03 14:24:27
  • Explore the inner workings of Maven: a detailed explanation of build, dependency management and deployment
    Explore the inner workings of Maven: a detailed explanation of build, dependency management and deployment
    In-depth analysis of Maven: construction, dependency management and deployment Introduction In recent years, the software development industry has developed rapidly, and more and more projects require construction, dependency management and deployment. In this process, Maven is widely used as a popular build tool. This article will provide an in-depth analysis of the importance and usage of Maven's construction, dependency management, and deployment to help readers better understand and apply Maven. 1. Overview of Maven Maven is an open source project management and build tool that can help development teams
    javaTutorial . ssh 774 2024-01-03 10:24:03
  • What exactly is the reason for Kubernetes' widespread popularity?
    What exactly is the reason for Kubernetes' widespread popularity?
    Introduction The Kubernetes platform that runs containerized workloads plays a significant role when developing and deploying cloud-native applications. Naturally, developing and deploying cloud-native applications has become extremely popular. There are obvious advantages to a process that allows for rapid deployment and continuous delivery of bug fixes and new features, but no one talks about the chicken and egg problem: How to achieve this? Building the infrastructure and development processes to develop and maintain cloud-native applications from scratch is a non-trivial and time-consuming task. Kubernetes is a relatively new platform for running containerized workloads that solves these problems. It was originally a project within Google, and Kubernetes was developed in the 20s
    LINUX . ssh 1709 2024-01-03 08:30:03

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