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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 run a server on port 80 as a normal user on Linux?

I have Googled about a solution for quite some time, but couldn't find an answer. I am on Ubuntu Linux and want to run a server on port 80, but due to security mechanism of Ubuntu, I get the following error: java.net.BindException: Permission…
Deepak Mittal
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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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Linux FHS: /srv vs /var ... where do I put stuff?

My web development experience has started with Fedora and RHEL but I'm transitioning to Ubuntu. In Fedora/RHEL, the default seems to be using the /var folder while Ubuntu uses /srv. Is there any reason to use one over the other and where does the…
wag2639
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Linux: How to know where a process was started and how it was started?

I was checking a Linux box and found a perl process running and taking a good share of cpu usage. With top, i could only perl in process name. When i pressed c, to view the command-line, it showed /var/spool/mail. Which does not make sense, since…
Fernando
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Hidden Features of Linux

Following in the spirit of Hidden Features of PowerShell and various others on Stack Overflow, what Linux commands or combinations of commands do you find essential in your work? Also See: Hidden Features of MySQL Hidden Features of PowerShell…
Chris Bunch
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shutdown: What is difference between "Power Off" and "Halt"?

With your typical Linux shutdown command, what is the difference between halting the system and powering off the system?
Jake Wilson
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How to grep ps output with headers

How can I grep the PS output with the headers in place? These two process make up an app running on my server.... root 17123 16727 0 16:25 pts/6 00:00:00 grep GMC root 32017 1 83 May03 ? 6-22:01:17…
Ben
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how can I schedule a reboot in Linux?

I'm new in Linux and I want to schedule a reboot at midnight. How should I do it? Edits: I'm sorry I didn't put the complete details. I want a reboot every 3rd Saturday of the month at 23:30. I don't know what's wrong but I cannot find crontab.…
klauriens
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What is the maximum username length on current GNU/Linux systems

I'd like to know what the maximum username length is for current GNU/Linux systems, e.g. Ubuntu 11.04. 8 characters appears to be some historical standard, but I've already noticed on my current Ubuntu system that this limit does not apply.
Klaas van Schelven
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What can cause a signal 11?

What is the most likely causes of signal 11, also know as "segmentation fault"?
jpmartins
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How often should I reboot Linux servers?

I have many Linux servers (SUSE 9 &10) used to run web services that provide data to large calculation grids. Recently we have had some difficult to explain outages (i.e. hardware and software logs are not showing any obvious errors) and we are…
John Channing
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Who last modified file?

Is there a way to tell who (which user) last modified the last file in Linux (RHEL)?
wag2639
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How to compare differences between directories (linux)

I have two directories - one from earlier backup and second from newest backup. How do i compare what changes were made to files in directory from newest backup on Linux? Also how do i display changes in for example text and php files - i'm thinking…
Phil
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How do I append a specific number of null bytes to a file?

I have a script that writes to a few files but I need them a specific size. So I'm wondering if there's a way of appending a specific number of null bytes to a file by using standard command line tools (e.g, by copying from /dev/zero)?
incognito2
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How do I get Centos VM to re-read its increased Disk size WITHOUT a reboot

I have a CentOS 5 VM and I've just increased the VM disk from 10G to 20G, but I cannot get fdisk to see the new disk size without a reboot. I've tried echo 1 > /sys/block/sda/device/rescan, it seems to indicate it can see the new size, but when I go…
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