Category : Systems


How to Install Kubernetes on CentOS 7 (Step by Step) Introduction Small virtual environments, called containers, have become indispensable for developing and managing applications. Working on applications within an isolated container does not affect the host operating system. Containers are more efficient than virtual machines as they do not need their operating system. Kubernetes is ..

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FFmpeg is a free and open-source collection of tools for handling multimedia files. It contains a set of shared audio and video libraries such as libavcodec, libavformat, and libavutil. With FFmpeg, you can convert between various video and audio formats, set sample rates, capture streaming audio/video, and resize videos. This tutorial walks you through installing ..

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A sample service check, annotated:    host_name                       dbsrp2076                  <– name of server     service_description             SSH                        <– service being monitored     servicegroups                   PROD-ssh                   <– service groups     is_volatile                     0                          <– Does this service spontaneously start and stop (always 0 for “no”)     check_period                    24×7                       <– during what hours is this service checked?     max_check_attempts              10                         <– ..

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What if Windows let you quickly access administrative tools, backup and restore options and other important management settings from a single window? If that sounds good, look no further than the so-called “God Mode.” What Is God Mode? No, God Mode doesn’t unlock any extra secret features in Windows or let you do any tweaking ..

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Most distributions of Linux come with a handy network latency utility called mtr.  Thankfully, it is included with the distributions of RHEL we use as well.  It’s a combination of ping and traceroute which show each hop of a network path, the time for that hop, and averages/standard deviations.  I use it all the time.  ..

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From screentogif.com: This free tool was (and still is) mainly projected to work as a quick and small screen recorder. If you plan to record hours of fullscreen content, I recommend switching to more advanced software. Recording 📹 ScreenToGif allows you to record part of your screen with the Screen Recorder, also there’s the Webcam ..

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Nikto is a very popular and easy to use webserver assessment tool to find potential problems and vulnerabilities very quickly. This tutorial shows you how to scan webservers for vulnerabilities using Nikto in Kali Linux. Nikto comes standard as a tool with Kali Linux and should be your first choice when pen testing webservers and web applications. ..

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By far the simplest option is for Mac users to install Telnet through Homebrew. If you haven’t done so, go through these steps first: Next, from a termina window, run this command. brew install telnet Hit Return and let Homebrew download and install Telnet to the Mac When installation has complete, you can run Telnet ..

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Advanced Mac users may appreciate using the Homebrew package manager, which greatly simplifies the process of installing command line software and tools on a Mac. For example, if you want to easily install favorite command line tools on a Mac like cask, htop, wget, nmap, tree, irssi, links, colordiff, or virtually any other familiar unix ..

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To view the existing routes, C:\> route print To add a static route, Syntax: C:\> route add <target> mask <netmask> <gateway IP> metric <metric cost> if <interface> Example: C:\> route add 10.10.10.0 mask 255.255.255.0 192.168.1.1 metric 1 Note: If there is more than one Network Interface and if the interface is not mentioned, the interface ..

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BASH Shell Redirect Output and Errors To /dev/null How do I redirect output and errors to /dev/null under bash / sh shell scripting? How do I redirect the output of stderr to stdout, and then redirect this combined output to /dev/null? You can send output to /dev/null, by using command >/dev/null syntax. However, this will ..

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If you, or your clients, are unable to login to your/their email accounts and the system shows this error message: Plaintext authentication disallowed on non-secure (SSL/TLS) connections If you do not want to use SSL/TLS connection to get your email, and to disable SSL/TLS secure connection, do the following: 1. Edit dovecot configuration file: /etc/dovecot.conf ..

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This is a simple script that interactively converts an IP address to its decimal equivalent. This can sometimes be used to bypass web content filtering devices as not all will convert the decimal to an IP and then a hostname. #!/usr/bin/perl # # prompt for an IP print “Enter an IP Address: “; # get ..

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1. Determine what existing range files exist: # cd /etc/sysconfig/network-scripts/ # ls ifcfg-eth1-range* You will see at least one file, possibly several. Find the highest number following the “range” and add one to it. This will be the new range number. For example, if you see ifcfg-eth1-range0 and ifcfg-eth1-range1, your new range number will be ..

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Below is a fairly comprehensive list of most widely used performance testing tools for measuring web application performance and load stress capacity, current as of this post date (2012-09-19). These load testing tools will ensure your application performance in peak traffic and extreme stress conditions. The list includes open source as well as licensed performance ..

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Possible telnet test output for another database and their meaning is listed below: a) Result when firewall is blocking connection for a IP and port combination: >telnet 20.25.127.140 3306 Trying 20.25.127.140… telnet: Unable to connect to remote host: Connection timed out b) Result when firewall is allowing connections through for IP address and port number ..

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Commands that can be run from the command prompt The List Accessibility Controls access.cpl Add Hardware Wizard hdwwiz.cpl Add/Remove Programs appwiz.cpl Administrative Tools certmgr.msc Calculator calc Character Map charmap Check Disk Utility chkdsk Clipboard Viewer clipbrd Command Prompt cmd Component Services dcomcnfg Computer Management compmgmt.msc Date and Time Properties timedate.cpl DDE Shares ddeshare Device Manager ..

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A whole bunch of Windows command line shortcuts: Accessibility Controls access.cpl Add Hardware Wizard hdwwiz.cpl Add/Remove Programs appwiz.cpl Administrative Tools certmgr.msc Calculator calc Character Map charmap Check Disk Utility chkdsk Clipboard Viewer clipbrd Command Prompt cmd Component Services dcomcnfg Computer Management compmgmt.msc Date and Time Properties timedate.cpl DDE Shares ddeshare Device Manager devmgmt.msc Direct X ..

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