Linux Command Line Cheat Sheet

https://www.networkworld.com/article/3337516/linux/the-linux-command-line-cheat-sheet.html

Understanding what "Everything is was a file" means in UNIX/Linux

Understanding what "Everything is was a file" means in UNIX/Linux

This is and was a key concept of UNIX, and therefore Linux since their inception. Recently however this idea has been heavily shat upon by systemd's designers and as this blight's mission creep continues to take over more and more utterly init unrelated systems and processes, more of the "Everything is a file" simplicity and power of Linux is destroyed.

#Linux

More on Linux files and hard and soft links here:
https://www.tecmint.com/create-hard-and-symbolic-links-in-linux/#
https://www.tecmint.com/explanation-of-everything-is-a-file-and-types-of-files-in-linux/

Advanced Linux - using TCP BBR

Advanced Linux - using TCP BBR

I've looked at BBR and it certainly looks like a great innovation in network performance. That said I only recommend its use right now by advanced Linux admins with a pressing need for the improved performance, and then only after serious load testing on non critical network links.
For everyone else I recommend you wait until it is integrated into your Linux distribution and the mainline kernel. That way you are not messing with your vendor's highly tuned and optimized kernel configuration and you're getting something tested and integrated into the system as a whole.

#Linux #SysAdmin #Networking
https://www.cyberciti.biz/cloud-computing/increase-your-linux-server-internet-speed-with-tcp-bbr-congestion-control/

OpenSUSE ups the security game in Tumbleweed with PIE support enabled as the default for all binaries

OpenSUSE ups the security game in Tumbleweed with PIE support enabled as the default for all binaries

FTA:
"Tumbleweed is now built with PIE (Position Independent Executables) as default. [...] This allows full ASLR (address space randomization) for all binaries without specific need to change your actual package, making attacks much harder,"

#Linux #Security #OpenSUSE
http://news.softpedia.com/news/opensuse-tumbleweed-os-is-now-built-with-pie-as-default-for-increased-security-516527.shtml?utm_content=buffer68f37&utm_medium=social&utm_source=plus.google.com&utm_campaign=buffer

Linux Tips & Tricks - Using alias

Linux Tips & Tricks - Using alias

While alias is a great way to shorten commonly used commands, I rarely recommend that people do so. Why? Because those alias' won't be on any other system you might use and it's easy to forget the syntax of the original commands they replaced. I especially don't recommend this for consultants and admins that work on a lot of other systems for this reason. It becomes a crutch that you will not have anywhere but on your machines.
However, I've posted this anyway because there are certainly cases where it's very useful. Just be careful to use them sparingly, only where necessary, and only on systems that you use constantly.

#Linux
https://opensource.com/article/17/5/introduction-alias-command-line-tool

Linux box won't boot? - Revive a dead grub with these tips

Linux box won't boot? - Revive a dead grub with these tips

If you use computers long enough that you've installed Linux on, you'll probably have this happen to you eventually. The easiest way in the past has been to try installing a dual boot Windows and Linux system and forgetting to install Windows first. However there are other ways it can happen
Here are several solutions, pick one and try it.

#Linux #Windows
http://www.linuxandubuntu.com/home/ways-to-rescue-or-recover-grub-menu

Learning Linux - Mastering the Command Line: Comparisons in Bash

Learning Linux - Mastering the Command Line: Comparisons in Bash

At some point in your Linux journey you'll start creating shell scripts, and at some point in that process you'll find it necessary to perform logical comparisons. Is this bigger than that? Is that the same as this? And so on. Here's a tutorial to get you started.

#Linux #CommandLine #Sysadmin
http://www.linuxtechi.com/compare-numbers-strings-files-in-bash-script/

Linux Tips & Tricks - Monitoring disk space from the command line with ncdu

Linux Tips & Tricks - Monitoring disk space from the command line with ncdu

ncdu is a great tool for Linux users in general, but especially for sysadmins that administer machines remotely via ssh.
It's a way to view your systems disk usage in a semi-graphical way from a simple ncurses based command line tool.

#Linux #Sysadmin
https://www.ostechnix.com/check-disk-space-usage-linux-using-ncdu/

Linux command line - Having a little fun

Linux command line - Having a little fun

The command line isn't all work, there's fun stuff too.

#Linux
http://www.linuxtechi.com/12-interesting-linux-commands-make-you-laugh/

Learning Linux, command line tips & tricks - Mastering the find command

Learning Linux, command line tips & tricks - Mastering the find command

If you've only used the GUI search functions of your desktop OS, you will be amazed at the power of the 'find' command on Linux and Unix.
It's extremely powerful and flexible and you won't know how you got along without it once you learn it.

#Linux

https://www.howtoforge.com/tutorial/linux-find-command/

Learning Linux - Alternative shells

Learning Linux - Alternative shells

A lot of people don't even think about what the Linux command line is or that there are multiple versions of it. But the command line interpreter, or shell, is just a program like any other and like most programs, there are alternatives to the default.
The truth is that even advanced Linux administrators rarely use much other than Bash, but it does pay to know the alternatives that are out there and a little bit about them, particularly if you'll be working with UNIX systems as well as Linux.

#Linux
https://www.maketecheasier.com/alternative-linux-shells/

Linux Tips & Tricks - mastering the command line - limiting the bandwidth of rsync

Linux Tips & Tricks - mastering the command line - limiting the bandwidth of rsync

If you've been using Linux seriously at all for any length of time, you're using rsync to copy, move, or back-up files. However sometimes for long remote transfers you don't want rsync hogging up all of your bandwidth. But you can force rsync to only use a portion of your bandwidth, allowing you to run it in the background while you carry on with your business.

#Linux

https://www.cyberciti.biz/faq/how-to-set-keep-rsync-from-using-all-your-bandwidth-on-linux-unix/

Network bonding with Linux

Network bonding with Linux

Sysadmins have been using this trick for years to get their own, inexpensive, custom, high speed network links. A primary example is from a server to a NAS device. Or a server to a backplane switch that supports bonding.
These days there are even ways to bond ISP connections to increase bandwidth if you're lucky enough to have an ISP that supports bonding.

So read on and find out how to do network bonding on Linux.



#Linux #sysadmin #Networking
http://kerneltalks.com/other/network-bonding-teaming-configuration-in-linux/

Learning Linux - Command line skills: Deleting a command from your bash history

Learning Linux - Command line skills: Deleting a command from your bash history

Every Linux pro lives in their Linux shell history, it makes repetitive processes fast, easy, and accurate. However, there are plenty of times when you use a command that you really don't want in your history file. For example, suppose you had to use the dreaded rm -Rf . at some point? You certainly don't want that hanging around in your history where you may accidentally re-run it.
The problem is you don't want to just delete your whole shell history either. Well here's a tutorial on deleting specific lines from your bash history.

#Linux

https://www.ostechnix.com/clear-specific-command-bash-history-linux/

Shorewall Firewall configuration tool for Linux

Shorewall Firewall configuration tool for Linux

Shorewall is a great way to do your own detailed, customized, firewall configuration. Just make sure before you use it that your distro doesn't have it's own, pre-loaded firewall configuration tool installed and already managing your firewall settings. OpenSUSE for example has it's own so read the OpenSUSE docs on how to properly disable it.

This would be especially handy for small, single purpose Linux system, eg a RasPi based firewall, but it's also a good tool for larger firewall setups too.

#Linux #Security #firewall
https://www.linux.com/learn/security/2017/2/introduction-shorewall-firewall-tool

Linux to the rescue! - Recover "lost" photos from memory cards

Linux to the rescue! - Recover "lost" photos from memory cards

We've all been there. Maybe you accidentally deleted more pictures than you meant to from your camera, or maybe the card got corrupted. Maybe you formatted it by mistake. Whatever happened, it can be heartbreaking and devastating depending on what was stored on the card. Some photos are just irreplacable. Weddings, vacations, and many other events with sentimental value. Or photos with monetary value if you're a pro photographer.
Luckily Linux can help. Because it's designed to let users and programmers do advanced things easily, Linux is a host for a plethora of great tools and utilities to fix and recover things from all manner of devices, even if those devices were used on other platforms.
So always keep at least a Linux rescue disk or USB stick on hand, because it may just save the day.

Here is just one of the amazing tools available on Linux for data recovery. Photorec.

#Linux   #DataRecovery   #Photography  
http://www.tecmint.com/photorec-recover-deleted-lost-files-in-linux/

Learning the Linux command line - shell commands

Learning the Linux command line - shell commands

In my ongoing quest to get people to actually learn Linux, which includes learning the command line as a requisite, I present this interesting article I found which explains some of the various categories of shell commands and their usage and purpose.

#Linux  
http://www.tecmint.com/understanding-different-linux-shell-commands-usage/

Making the most of Linux in a Windows world - WINE via Play On Linux

Making the most of Linux in a Windows world - WINE via Play On Linux
An OpenSUSE oriented HowTo

Like it or not, we live in a world in which Microsoft still has quite a hold on the computing desktop. While home users can happily run Linux and never even care that Windows exists, Enterprises and Gamers both face a reality in which some software is only produced for Windows and has no reasonable substitute (or their work can't/won't accept a substitute).
For these instances, there are a lot of options to stay with Linux, from running a full on Windows installation in a Virtual Machine using VirtualBox, VMWare or similar, to running individual software applications right on Linux using WINE. WINE is an amazing labour of love by generations of developers that allows a huge number of Windows applications to run directly on Linux with WINE acting as an intermediary between the application and Linux.
The problem with WINE is that it's a complex bit of kit with a powerful suite of options. This power also means it can be difficult to setup and requires a unique customization of settings for each application you install. Thankfully there are solutions to this problem as well. One such solution is Play On Linux which is a front end for WINE that not only provides a nice GUI front end for installing Windows applications, but it also pulls from a lovingly maintained online database of configuration settings for hundreds of Windows applications. Like the name implies, Play On Linux is geared towards installing Windows games, but it also has a solid set of configurations for many other types of Windows software, including a fair bit of productivity software like Microsoft Office, Adobe CS, etc.

You can go to the main post link and read more, including install sources for various Linux distros.

For OpenSUSE Linux users, keep reading, we're going to walk you through installing it

First, just a reminder that OpenSUSE has one of the largest pools of Linux software packages in the Linux world. The default repositories are quite large themselves, and adding the Packman repo from the Community Repositories section in YaST2 gets you that many more packages to pull from, but even those large pools of software don't have everything. So next we go to OBS, or the "OpenSUSE Build Service" which developers and savvy users can use to submit source packages and configure so that the OBS system can automatically build repos and packages for multiple Linux platforms, not just including several releases of OpenSUSE. Find OBS at:
https://software.opensuse.org/search

Now, for OpenSUSE Leap 42.x users, you can install Play On Linux using the following commands in a root shell (ie open a shell and type su followed by your root password).

Now type:
zypper ar http://download.opensuse.org/repositories/games:/tools/openSUSE_Leap_42.2/games:tools.repo
(all one line, then hit ENTER)
This will add the repository containing Play On Linux to your system.
Now type:
zypper in PlayOnLinux
This will install the package from the repository you just added.
It will ask you about the repository's key. I recommend you type "a" for Always and hit ENTER. This will accept the repository key permanently allowing it to be updated with each new update as part of your standard system updates process.
NOTE: The above is for those running OpenSUSE Leap 42.2. If you are running version 42.1 (type cat /etc/SuSE-release to verify) then simply edit the first line above starting with "zypper ar ..." and change the 42.2 part to 42.1.

Voila! You now have Play On Linux installed on your OpenSUSE Linux system. You can find it in the "System" section of the start menu. Run it and say yes to the data submission option to help the developers make the program better without submitting any personally identifying information.
From here on out you can get instructions on using Play On Linux at the main link below.
Oh, and keep in mind that you also need to have WINE installed (of course) and a few other dependencies that zypper can handle for you automatically.

#Linux   #Windows   #WINE   #OpenSUSE  
https://www.playonlinux.com/en/

Installing Google's "GO" programming language on Linux

Installing Google's "GO" programming language on Linux

For anyone interested in checking out the GO language under Linux, here's an article with some fairly generic instructions.

For OpenSUSE users it's much simpler.
Open a root shell and type
zypper in go
then approve the packages listed which should be "go" and "go-doc".
Enjoy.

#Linux   #development   #programming   #golang  
http://www.tecmint.com/install-go-in-linux/

Linux Tips & Tricks - Mastering the command line - SED

Linux Tips & Tricks - Mastering the command line - SED

Manipulating text in files is a common daily task for any sysadmin and learning to use the powerful tools available to do this can make an administrator's life vastly easier.
One of the most common and powerful tools for doing this is 'sed'.

Here's a sed tutorial to get you started.

Also note that sed has a partner 'awk' that is equally powerful in different ways. The two are often learned and used together.

To learn more about sed and awk, check out:
http://www.theunixschool.com/p/awk-sed.html
https://quickleft.com/blog/command-line-tutorials-sed-awk/
http://docstore.mik.ua/orelly/unix/sedawk/

#Linux   #Sysadmin   #CommandLine  
http://www.tecmint.com/linux-sed-command-tips-tricks/