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Questions tagged [linux]

Linux is the generic term for a UNIX-like open source operating system based on the Linux kernel.

GNU/Linux is a UNIX-like Open Source operating system. Linus Torvalds originally wrote the Linux kernel with contributions from others on the MINIX usenet board. Since then, Linux had thousands of developers, both paid by companies and volunteers. The main system tools and libraries for GNU/Linux are sourced from the GNU Project, hence the nomenclature GNU/Linux (GNU Toolchain over Linux Kernel). The Linux kernel is licensed under the GPL v2 license.

There are many different Linux Distributions (sometimes shortened to distro), which consist of software applications packaged and provided with the Linux kernel, being Slackware the oldest active distro and Debian, Red Hat and CentOS among the most used on Internet servers¹.

The Linux kernel is commonly run on servers but is highly portable and is used in a variety of applications, from wireless routers and cell phones to clusters and super computers with thousands of nodes and processors.

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How to disable everything in crontab -l?

I just want to pause everything. Don't execute anything listed on crontab -l.
Alex
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How bad is it really to install Linux on one big partition?

We will be running CentOS 7 on our new server. We have 6 x 300GB drives in raid6 internal to the server. (Storage is largely external in the form of a 40TB raid box.) The internal volume comes to about 1.3TB if formatted as a single volume. Our…
bdemarest
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How can I get processor/RAM/disk specs from the Linux command Line?

Possible Duplicate: How to find out details about hardware on the Linux machine? How can I get processor/RAM/disk specs from the Linux command Line?
yazz.com
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What is the maximum port number in Linux?

I'd like to set some Linux services to non-standard ports - what's the highest valid port number?
Yehosef
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How do I extract login history?

I need to know the login history for specific user (i.e. login and logout time), How do I extract this history for a specific date range in Linux ?
shox
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Caching/preloading files on Linux into RAM

I have a rather old server that has 4GB of RAM and it is pretty much serving the same files all day, but it is doing so from the hard drive while 3GBs of RAM are "free". Anyone who has ever tried running a ram-drive can witness that It's awesome in…
Andrioid
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Show all users and their groups/vice versa

I know I have existing groups and users but I'm not sure about their association. Is there an shell command I can use to list all users or all groups and a command to list all groups/users for a specified user/group? So something like showusers…
Steve Robbins
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How can I fully log all bash scripts actions?

From my script output I want to capture ALL the logs data with error messages and redirect them all to log file. I have script like below: #!/bin/bash ( echo " `date` : part 1 - start " ssh -f admin@server.com 'bash…
BlueMark
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Is it possible to reboot a Linux OS without rebooting the hardware?

Is there a way to reboot a Linux system (Debian in particular) without rebooting the hardware? I have a RAID controller that takes a bit to get itself running before the OS starts up, and I would like it if there was a way to quickly reboot the…
lacrosse1991
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swap partition vs file for performance?

What is better for performance? A partition closer to the inside of the disk will have slower access times, and we must wait for the drive to switch between the OS and swap partitions. On the other hand, a swap partition bypasses all of the…
Bill Gray
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GPG does not have enough entropy

I've got a ton of processes running in the background to try and get enough entropy, but I am still failing. **We need to generate a lot of random bytes. It is a good idea to perform some other action (type on the keyboard, move the mouse, utilize…
Joey BagODonuts
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Linux - Is there a way to prevent/protect a file from being deleted even by root?

I have a very important file which an application in my workplace uses, i need to make sure it is not delete whatsoever, how can I do that?
user256033
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Why drop caches in Linux?

In our servers we have a habit of dropping caches at midnight. sync; echo 3 > /proc/sys/vm/drop_caches When I run the code it seems to free up lots of RAM, but do I really need to do that. Isn't free RAM a waste?
ivcode
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Why don't EC2 ubuntu images have swap?

I started a couple servers on EC2 and they don't have swap. Am I doing something wrong or is it that the machines just don't have any?
rafamvc
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How to determine the hostname from an IP address in a Windows network?

My LAN has 50 Windows hosts. At the Windows command line I try ping to get the IP address of a running Windows machine. The question is how to get hostname of a specific IP address in the same Windows workgroup? Another question is how to know the…
billyduc
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