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Using SSH keys for Password-less Logins

Using SSH keys for Password-less Logins
Most people start using SSH by logging in with a password, but re-entering your password for every SSH connection quickly becomes tedious. A better way is to set up a public/private key pair - you unlock your key once and then reuse it to make connections without entering your password. It may sound a bit complicated but you can set it up with two simple commands* ssh-keygen ssh-copy-id hostname You run the first command once to set up your public/private key pair and then you run the second command once for each host you want to connect to. These steps are spelled out in more detail below, but those two commands are all you need to get going. * This guide assumes you're running GNOME on a modern desktop Linux distribution such as Ubuntu, Debian, Fedora etc. Step 0: Think of a password Before we start with step 1, you'll need to think of a password. It's always difficult to think up a new password. Step 1: Generate a key pair ssh-keygen You'll be prompted for a filename - just press Enter. Related:  Linux

An A-Z Index of the Bash command line for Linux Commands marked • are bash built-ins Many commands particularly the Core Utils are also available under alternate shells (C shell, Korn shell etc). More bash commands: Linux Command Directory from O'Reilly, GNU CoreUtils.SS64 bash discussion forumLinks to other Sites, books etc Linux PC+ Linux tips every geek should know What separates average Linux users from the super-geeks? Simple: years spent learning the kinds of hacks, tricks, tips and techniques that turn long jobs into a moment's work. If you want to get up to speed without having to put in all that leg-work, we've rounded up over 50 easy-to-learn Linux tips to help you work smarter and get the most from your computer. Enjoy! UPDATE: If these tips aren't enough and you want even more, make sure you check out More Linux tips every geek should know! #1: Check processes not run by you Difficulty: Expert Application: bash Imagine the scene - you get yourself ready for a quick round of Crack Attack against a colleague at the office, only to find the game drags to a halt just as you're about to beat your uppity subordinate - what could be happening to make your machine so slow? OK, let's list all the processes on the box not being run by you! ps aux | grep -v `whoami` Or, to be a little more clever, why not just list the top ten time-wasters: find . reset

Vector Linux review After a very busy month, I finally had some free time to try Vector Linux, a distro that a facebook friend told me to take a look at. For those of you that dont know, Vector Linux is a distro that has been around for quite a long time. It is based on Slackware, with Xcfe, KDE and LXDE as the available desktop environments. According to the official website, the aim of Vector is to keep the distro simple and small and let the end user decide what their operating system is going to be. Download and first impressions The download page of Vector Linux will remind you of Windows, there are several editions for you to download. As usual, I used Unetbootin to create the live USB. You can test Vector Linux on live mode just like other distros. Installation The installation process of Vector Linux seems to me quite complicated with many redundant steps. First of all, after I clicked on the "Install VL" option, a dialog box will appear to ask for the root password of the live CD: The desktop

What Is Btrfs Filesystem (and Why Is It Better Than Ext4)? There is more to a hard drive than its size. While the amount of disk space is all you see marketed about a hard drive on a sales page, there is actually an extensive amount of coding that goes into making a hard drive capable of handling your applications and data in the first place. Most Linux distributions currently default to using the ext4 file system, but the future for many of them lies with the B-tree file system, better known as Btrfs. To put it simply, a file system is how a hard drive is able to store, access, and manage files. While different operating systems can run off of the same hard drive, they tend not to share the same file system. Windows users rely on the New Technology File System (NTFS) while Mac OS X currently runs on the HFS+ file system. Btrfs is a modern file system that began development back in 2007. Btrfs is not a successor to the default Ext4 file system used in most Linux distributions, but it can be expected to replace Ext4 in the future.

All the Best Linux Cheat Sheets Linux Security Quick Reference Guide - An awesome security checklist reference IP Tables - If you are interested in Linux firewalls this is a must have TCPDump - Great cheat sheet to an awesome security tool Wireshark Filters - An awesome list of filters for the best packet sniffing utility IP Access Lists - Cheat sheet for IP Access Lists Common Ports - In case you don’t have all common ports memorized netcat - Reference to the swiss army knife of networking

10 must-have Linux desktop enhancements Among the variety of enhancements for the Linux desktop, there are a few gems that will really blow you away. Jack Wallen pinpoints some additions you'll definitely want to try. If you haven't experienced the Linux desktop as offered by one of the more recent distributions, you don't know what you're missing. Not only is the default desktop a thing to behold, it also allows for the addition of some amazing enhancements. From eye candy to tools that make your work more efficient, the Linux desktop can be expanded to include just about anything you want. I'm going to share some desktop enhancements that will make your Linux desktop experience far better. Note: This article is also available as a PDF download. 1: Compiz Compiz is to the Linux desktop as HiDef is to the world of television. 2: Screenlets Screenlets are tiny applications that live on your desktop and provide extra functionality. 3: Emerald Emerald is a window decorator written for the Compiz compositing window manager. 4: Cairo

VirtualBox VirtualBox 5.1.12 for Linux ¶ Note: The package architecture has to match the Linux kernel architecture, that is, if you are running a 64-bit kernel, install the appropriate AMD64 package (it does not matter if you have an Intel or an AMD CPU). Mixed installations (e.g. Debian/Lenny ships an AMD64 kernel with 32-bit packages) are not supported. To install VirtualBox anyway you need to setup a 64-bit chroot environment. The VirtualBox base package binaries are released under the terms of the GPL version 2. Please choose the appropriate package for your Linux distribution: You might want to compare the SHA256 checksum or the MD5 checksum to verify the integrity of downloaded packages. Oracle Linux ¶ Users of Oracle Linux 5, 6 and 7 can use the public yum repository and enable the el5_addons (OEL5), the ol6_addons (OL6) or the ol7_addons (OL7). yum install VirtualBox-5.1 to the latest maintenance release of VirtualBox 5.0.x. Debian-based Linux distributions ¶ You can add these keys with

UNIX tips: Learn 10 good UNIX usage habits Break bad UNIX usage patterns Michael StutzPublished on December 12, 2006 When you use a system often, you tend to fall into set usage patterns. Sometimes, you do not start the habit of doing things in the best possible way. Sometimes, you even pick up bad practices that lead to clutter and clumsiness. Adopt 10 good habits Ten good habits to adopt are: Make directory trees in a single swipe Listing 1 illustrates one of the most common bad UNIX habits around: defining directory trees one at a time. Listing 1. It is so much quicker to use the -p option to mkdir and make all parent directories along with their children in a single command. Listing 2. You can use this option to make entire complex directory trees, which are great to use inside scripts; not just simple hierarchies. Listing 3. In the past, the only excuse to define directories individually was that your mkdir implementation did not support this option, but this is no longer true on most systems. Listing 4. Listing 5. Listing 6.

PID EINS! If you are well connected or good at reading between the lines you might already know what this blog post is about. But even then you may find this story interesting. So grab a cup of coffee, sit down, and read what's coming. This blog story is long, so even though I can only recommend reading the long story, here's the one sentence summary: we are experimenting with a new init system and it is fun. Here's the code. Process Identifier 1 On every Unix system there is one process with the special process identifier 1. Historically on Linux the software acting as PID 1 was the venerable sysvinit package, though it had been showing its age for quite a while. As mentioned, the central responsibility of an init system is to bring up userspace. For a fast and efficient boot-up two things are crucial: To start less. What does that mean? Hardware and Software Change Dynamically Parallelizing Socket Services But first, let's clear a few things up: is this kind of logic new? Parallelizing Bus Services

WinUSB: Create Bootable Windows Installer USB In Ubuntu Linux WinUSB is an Ubuntu application for creating a Windows USB installer for Windows Vista and Windows 7. Like other applications that enable creating installer USBs, you can create a bootable (installation) USB from an ISO disc image or a DVD. While other tools like Unetbootin can perform similar tasks, however, WinUSB is much simpler than other competitors, and delivers a two-click solution for creating a Windows installer USB. To create your bootable installer disc, select an ISO image or CD/DVD disc, and click Install. This will create your Windows Vista/7 installer USB. sudo add-apt-repository ppa:colingille/freshlight sudo apt-get update sudo apt-get install winusb Since WinUSB also works from the command line, you can create a Windows 7 or Windows Vista USB installer by following the command line format given below: sudo winusb --format <iso path><device> Once the USB is formatted using the above method, install a Windows partition and edit the Master Boot Record: [via WEBUPD8]