In this post, how to unified Linux login and home directory using OpenLDAP and NFS/automount will be introduced. 0. System environment This solution is tested on Fedora 12 systems and CentOS 5. LDAP and NFS server: IP: 10.0.0.2 OS: Fedora 12 x86_64 ldap base dn: “dc=lgcpu1″ Clients: IP: 10.0.0.1/24 OS: Fedora 12 x86_64 1. LDAP
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Author: Eric Ma
Eric is a systems guy. Eric is interested in building high-performance and scalable distributed systems and related technologies. The views or opinions expressed here are solely Eric's own and do not necessarily represent those of any third parties.Linux UDP Programming Tutorial
Posted onUDP has its advantages over TCP, such as being relatively lightweight and receiving one packet per read call (recvmsg), although the programmers need to handle related issues, such as packet lost and out-of-order packets delivery. This post gives information and references on how to write UDP programs in a C/Linux environment. What is UDP Check
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How to Measure Time Accurately in Programs
Posted onIt is quite common to measure the time in programs using APIs like clock() and gettimeofday(). We may also want to measure the time “accurately” for certain purposes, such as measuring a small piece of code’s execution time for performance analysis, or measuring the time in time-sensitive game software. It is hard to measure the
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Favorite Sayings by John Ousterhout – Precious Experience and Advice for Building Systems
Posted onJohn Ousterhout is a professor of Deparment of Computer Science from Stanford University. One recent project he is working on is the RAMCloud, a “new class of storage, based entirely in DRAM, that is 2-3 orders of magnitude faster than existing storage systems”. He posts his “Favorite Sayings” on his homepage. These sayings are precious
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How to Bypass Bad fstab Failure When Booting Linux
Posted onIf /etc/fstab file is created with errors or the hardware configuration changes such as adding hard disks, Linux will boot into failure state. We can bypass the fstab failure by adding booting parameters to Linux. We can do this in two methods: Method 1: Boot to single user mode When booting into single user mode,
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Changing Linux User Password in One Command Line
Posted onIn Linux, we use passwd to change password, but passwd requires input from stdin to get the new password. It is common case that we may want to change the password non-interactively, such as creating new user accounts and change or set password for these accounts on a number of Linux boxes when the new
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Effective Anti-Spam in WordPress with Plugins
Posted onWordPress has a very rich set of plugins and a combination of them can make anti-spam in WordPress quite easy. Here is a list of plugins that can help prevent spammers from registering spam account (if the site allows registration of new users) and posting spam comments. Anti spam comments Use the Akismet WordPress plugin.
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How to Configure iOS to Use Socks Proxy over SSH with a Linux/Unix Host
Posted onThe socks proxy I created following Proxy Using SSH Tunnel works very well on both Linux and Windows. However, when I try to configure my iPhone and iPad with iOS, I find iOS does not support socks proxy in its settings interface. I don’t know why it is not added while socks proxy is indeed
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Software Engineering Advice from Building Large-Scale Distributed Systems by Jeff Dean
Posted onSoftware Engineering Advice from Building Large-Scale Distributed Systems by Jeff Dean. You can download the slides from Software Engineering Advice from Building Large-Scale Distributed Systems by Jeff Dean. These slides contain the “Numbers everyone should know” which everyone working on systems should be familiar with. Numbers Everyone Should Know L1 cache reference 0.5 ns Branch
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How to Copy Output of Commands in a Linux Terminal to X Selection or Clipboard
Posted onxclip is a tool to copy the copy the output of commands from a command line in a terminal to X selection or clipboard. It connects the command line interface and the X selections (clipboard) and is a very useful tool. For example, processing some text in vim in a terminal and then copying it
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Hadoop MapReduce Tutorials
Posted onHere is a list of tutorials for learning how to write MapReduce programs on Hadoop, the opensource MapReduce implementation with HDFS. MapReduce Tutorials The official tutorial on Hadoop MapReduce framework: http://hadoop.apache.org/docs/r1.0.4/mapred_tutorial.html. Yahoo! Hadoop Tutorial A comprehensive tutorial on Hadoop from Yahoo! Developer Network: http://developer.yahoo.com/hadoop/tutorial/. More about MapReduce To better understand the design behind MapReduce, it
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How to Change MediaWiki’s Main Page Title and URL
Posted onMediaWiki set’s the default page (the homepage) to the “Main Page” by default. The name “Main Page” is too general and does not give more meanings. Usually for a specific site, we may change it to some meaningful name and URL. This is a configurable in MediaWiki. This tutorial introduces how to change MediaWiki’s Main
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How to Change MediaWiki’s Sidebar
Posted onMediaWiki’s Sidebar can be configured as a special page. This page’s title is “MediaWiki:Sidebar”. For example, if a MediaWiki site www.example.com is configured to use [[search-engine-friendly-url-for-mediawiki]], the URL for edit the Sidebar is: http://www.example.com/w/MediaWiki:Sidebar It may look like this: * navigation ** mainpage|mainpage-description ** recentchanges-url|recentchanges ** randompage-url|randompage ** currentevents-url|currentevents ** portal-url|portal ** helppage|help * SEARCH
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Proxy using SSH Tunnel on Windows
Posted onThis article is an instruction of how to use https://www.systutorials.com/proxy-using-ssh-tunnel/ on a Windows machine. The mechanism is similar as the one in https://www.systutorials.com/proxy-using-ssh-tunnel/ with “Proxy listening to localhost port only”. Download PuTTY PuTTY is the software we use here for port forwarding. Please download it following the links in https://www.systutorials.com/open-source-and-portable-ssh-scp-sftp-and-vnc-clients-for-windows-to-remote-control-linux/. Configure PuTTY and create a
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How To Set Mobile Skin for MediaWiki
Posted onMore and more users are browsing the Internet using a mobile device. It is preferred to provide good experience for these users. One method to service a mobile version of the page to a user with a mobile device. This tutorial introduces how to add mobile skin support for MediaWiki. Skin for mobile devices I
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Search Engine Friendly URL for MediaWiki
Posted onMediaWiki is the wiki-engine that runs Wikipedia. In this tutorial, we introduce how to configure search engine friendly URLs in MediaWiki. ==Search Engine Friendly URLs== Default MediaWiki URLs look like www.example.com/w/index.php?title=TITLE which is a little ugly. To make it more search engine friendly, we will change it to SEO-friendly URLs like www.example.com/w/TITLE. ==Enabling Search Engine
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How To Mount Google Drive on Linux
Posted onGoogle Drive is nice cloud storage which provide document editing features. However, it does not yet provide a Linux client. I find a good third party tool that works with Google Drive on Linux very well: google-drive-ocamlfuse. The website of google-drive-ocamlfuse provides easy to follow instructions to install it. In this tutorial, we show a
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Auto Keyboard Pressing Using xvkbd in Linux
Posted onAutomatic keyboard pressers are useful tools. However, it seems that there is no simple and easy to use automatic keyboard presser for Linux if you search for “automatic keyboard presser linux”. After some digging, I find using the xvkbd with some options is a good method for automatic keyboard pressing though it is not designed
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How to install no-ip client on Linux
Posted onnoip2 is a dynamic update client for No-IP to keep your current IP address synchronized with your No-IP domain, no matter whether the IP is dynamically requested via DHCP or static assigned. Furthermore, with the domain name, we can host site using a “static” domain whose CNAME points to the No-IP domain. noip2 is a
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ASCII Table and ASCII Code
Posted onThis post gives the ASCII table and ASCII code with ASCII control characters and ASCII printable characters and a tool to convert ASCII codes to ASCII characters. Introduction to ASCII table and ASCII code ASCII stands for American Standard Code for Information Interchange. An ASCII code is the numerical representation of a character since computers
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