I know the routing tables on Linux is in memory after being set. However, where are the routing table entries stored on disk? I mean where are the routing table is persistently stored so that the routing table can be reloaded like the iptables (under /etc/sysconfig/iptables on Fedora/RHEL/CentOS Linuxes). If the system uses the /etc/rc.d/init.d/network
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Tag: Command
How to use OCaml as a script language?
Posted onHow to use OCaml as a script language like bash and python? It will be good that I can write a script in OCaml and directly invoke it. For example, I write a script named “script.ml” and then I can invoke it directly by $ ./script.ml Thanks! Three helloworld scripts: script3.ml #! /usr/bin/env ocaml print_string
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How to set Google Chrome’s proxy settings in command line on Linux?
Posted onHow to set Google Chrome’s proxy settings in command line on Linux? I am using Google Chrome on Linux and start it by google-chrome. How can I set the proxy using the command line? It tell me that my desktop is not supported but I can set the proxy in command line. Use the –proxy-server
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How to restart Gnome 3 without closing the programs running?
Posted onWhat I want is to just restart Gnome 3 only and not to close and reopen the programs running. Thanks a lot! Just run r in Gnome 3’s “Run command” Box: Alt + F2, then enter r and hit Enter. Gnome 3 will restarts itself only.
Chrome’s KDE proxy integration broken on KDE / Fedora
Posted onChrome reads the proxy settings from Gnome correctly. However, when I run Chrome under KDE, the proxy integration is broken: In the settings of Chrome, clicking the “Change proxy settings” opens the KDE proxy setting dialog correctly (the command kcmshell4 proxy actually is executed). However, after the proxy settings are made, Chrome does not read
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How to activate or deactivate a Linux host with Gnome remotely?
Posted onI have a Fedora Linux server with Gnome 3. I want to lock / unlock the remote Gnome desktop remotely. How to activate or deactivate it remotely through SSH? Use gnome-screensaver-command. It is not specific to Gnome 3. Turn the screensaver on (blank the screen): $ gnome-screensaver-command -a If the screensaver is active then deactivate
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How to merge a commit from another branch to my current branch in git?
Posted onI have 2 branches: dev and master. I have commits in dev like this: c0–>c1–>c2–>c3–>c4 Commits in master like this: c0–>c5–>c6 c2 and c3 fix a bug. Now, I want to merge commit c2 and c3 that fix the bug to the master branch, but I do not want to merge all the commits (e.g.
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svn: how to clean up my repository directory?
Posted onI have a local svn repository. I work in the repository, e.g. compiling latex documents and building software packages, and there are many useless temporary files there. How can I clean it up by automatically clean these temporary files like the git clean -f in git? svn seems has no built-in function for this. But
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Make changes to sysctl.conf take effect without rebooting Linux?
Posted onI made some changes to /etc/sysctl.conf. I know it will take effect next time Linux boots. However, how to make the changes to sysctl.conf take effect without rebooting Linux? You can force Linux to reload the new configuration in /etc/sysctl.conf by: execute the following command as root: sysctl -p For more details, check the manual
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How to disable all swaps on Linux
Posted onHow to disable all swaps on Linux to force the application/kernel use the physical memory? To diable all swaps on Linux, run this command as root: # swapoff -a -a means all swaps. Similarly, to enable all swaps on Linux: # swapon -a
Enabling Debugging with CMake for a C++ Project
Posted onWhen developing a C++ project, debugging is an essential part of the process, as it allows you to identify and fix issues in your code. If you’re using CMake to build your project, it’s crucial to know how to enable debug mode to take advantage of debugging tools like gdb. In this post, we’ll walk
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Installing Latex and Compiling a Latex Docuent in Linux
Posted onLatex is a popular document preparation system that is widely used for creating scientific and technical documents. Compiling Latex documents on Linux is a straightforward process that requires only a few Latex packages and a set of commands. By following the steps outlined in this post, you can easily compile Latex documents on your Linux
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How to find Linux absolute path for a relative path
Posted onHow to find Linux absolute path for a relative path in Linux? We may need the absolute path on Linux when we only know the relative path. The readlink command does the trick. To find out the absolute path for a relative path, e.g. ./: $ readlink -f ./
Installing Dropbox on Linux
Posted onHow to install Dropbox on Linux ? Just follow Dropbox’s instruction here: https://www.dropbox.com/install?os=lnx A quick command for 64-bit Linux: $ cd ~ && wget -O – “https://www.dropbox.com/download?plat=lnx.x86_64” | tar xzf – Use the dropx CLI:Â http://www.dropboxwiki.com/Using_Dropbox_CLI Download dropbox.py: $ wget -O ~/bin/dropbox.py “https://www.dropbox.com/download?dl=packages/dropbox.py” Set the permissions: $ chmod +x ~/bin/dropbox.py Start Dropbox: $ dropbox.py start Status:
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How to Export an NFSv4 Server to External Networks
Posted onWe ever discussed fixing ports used by NFSv3 so that it can be easily exported to external networks. For NFSv4.1 or higher, things are much easier. The ports for mountd, statd, and lockd are not required in a pure NFSv4 environment. We have less ports to control or allow for connections. Only port 111 and
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How to force a metadata checkpointing in HDFS
Posted onThe metadata checkpointing in HDFS is done by the Secondary NameNode to merge the fsimage and the edits log files periodically and keep edits log size within a limit. For various reasons, the checkpointing by the Secondary NameNode may fail. For one example, HDFS SecondaraNameNode log shows errors in its log as follows. 2017-08-06 10:54:14,488
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Building and Installing Linux Kernel from the Source Code in an Existing Linux OS
Posted onBuilding Linux kernel may sound a complex and geek-only thing. However, as Linux kernel itself has much less depended tools/packages compared to other software packages, it is quite easy to compile, build and install a Linux kernel from the source code in an existing Linux OS. Building Linux kernel is needed if you need to
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Vim Tutorial for Beginners: vimtutor
Posted onThere are many Vim tutorials and Vim tips on the Web. However, I find the vimtutor provides the best tutorial among those so far as I found on the Web while the vimtutor seems usually reachable from a terminal which is not obviously known to Vim beginners who are usually Linux beginners too. This page
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Spring Shell Technology For Java development
Posted onThis post is about the Spring Shell technology and its use in java. Experts of java development India have shared their best knowledge in this post for Spring Shell with the community people. If you have anything to ask, do it at the end. Technology: It is command line tool for Java applications to interact
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The length of timeslices for processes under CFS process scheduling algorithm in Linux Kernel
Posted onAbstract As is known, CFS (Completely Fair Scheduling) is a famous process scheduling algorithm in Linux Kernel but there is no convenient way for developers to get the timeslices of processes if CFS is chosen. In this article, I will introduce one way to hack the timeslices of process easily for CFS in Linux Kernel.
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