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.

External Resources:

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Soft limit vs Hard limit?

Can anyone explain in layman's terms what the difference between soft and hard limit is? Should I set my soft and hard limit to be the same? Or should soft be significantly lower? Does the system benefit either way?
kidcapital
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rsync - Exclude files that are over a certain size?

I am doing a backup of my desktop to a remote machine. I'm basically doing rsync -a ~ example.com:backup/ However there are loads of large files, e.g. wikipedia dumps etc. Most of the files I care a lot about a small, such as firefox cookie files,…
Amandasaurus
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Why not block ICMP?

I think I almost have my iptables setup complete on my CentOS 5.3 system. Here is my script... # Establish a clean slate iptables -P INPUT ACCEPT iptables -P FORWARD ACCEPT iptables -P OUTPUT ACCEPT iptables -F # Flush all rules iptables -X # Delete…
Agvorth
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How to mount a VirtualBox shared folder?

What is the procedure for mounting a VirtualBox shared folder in Linux? I tried variations of the following mount command but I keep getting protocol error or other mount errors. sudo mount -t vboxsf share /home/toto
BSalita
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linux/setfacl - Set all current/future files/directories in parent directory to 775 with specified owner/group

I have a directory called "members" and under it there are folders/files. How can I recursively set all the current folders/files and any future ones created there to by default have 775 permissions and belong to owner/group nobody/admin…
Maverick
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Block select on a Linux console?

Is there any Linux console (konsole, gnome-terminal, etc.) that allows selecting text in a block mode, like you can in a Windows cmd.exe window, using Mark and drawing a rectangle?
Unknown
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What does mdev mean in ping(8)?

What does mdev mean in ping output (last row below)? me@callisto ~ % ping -c 1 example.org PING example.org (192.0.43.10) 56(84) bytes of data. 64 bytes from 43-10.any.icann.org (192.0.43.10): icmp_seq=1 ttl=245 time=119 ms --- example.org ping…
Daniel
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Bash find command verbose output

Is there way to tell the bash find command to output what it is doing (verbose mode)? For example for the command: find /media/1Tb/videos -maxdepth 1 -type d -mtime +7 -exec rm -rf {} \; to output: Found /media/1Tb/videos/102, executing rm -rf…
Alex
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How can I find current SSH protocol version of the current connection?

I connect to a Linux machine (CentOS 6.4) using PuTTY. Except from fact that I can set PuTTY to only use one type of protocol, how can I find the current SSH connection's version (SSH1 or SSH2)?
codiac
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How do I print contents of at jobs?

I have a Debian box with some jobs scheduled using at. I know I can list the jobs with their times using atq, but is there any way to print out their contents, apart from peeking into /var/spool/cron/atjobs?
che
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How do I make Linux recognize a new SATA /dev/sda drive I hot swapped in without rebooting?

Hot swapping out a failed SATA /dev/sda drive worked fine, but when I went to swap in a new drive, it wasn't recognized: [root@fs-2 ~]# tail -18 /var/log/messages May 5 16:54:35 fs-2 kernel: ata1: exception Emask 0x10 SAct 0x0 SErr 0x50000 action…
Philip Durbin
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How do I force Linux to reacquire a new IP address from the DHCP server?

The environment is Debian, although the answer will apply to all distributions.
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Why is my rsync so slow?

My Laptop and my workstation are both connected to a Gigabit Switch. Both are running Linux. But when I copy files with rsync, it performs badly. I get about 22 MB/s. Shouldn't I theoretically get about 125 MB/s? What is the limiting factor…
iblue
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What's the difference between apt-get and aptitude?

I don't get why there are two different programs in a minimal install to install software. Don't they do the same thing? Is there a big difference? I have read everywhere to use aptitude over apt-get but I still don't know the difference
Thomaschaaf
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how to run cron job every 3 months?

What would be the crontab entry look like for a job that runs on the first day of every third month?
haim evgi
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