Setting Up Linux Network Gateway Using iptables and route

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Sharing the networking is important and setting up a gateway is a good solution to it. Building up the gateway on a Linux box is easy, cost efficient and reliable. With a Linux box, you can share the internet connection or the only cable connected to the network. The Linux box network configuration The Linux
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Unified Xen DomU configuration file

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Previously, we create a configuration file for each DomU virtual machines in our cluster. Most of the content in these configuration files is the same. The differences are only the name, memory size and image file address. There are several disadvantages of this method: We must create and configure a new configuration file when creating
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Automatically Backing Up Xen File-backed DomU

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A script for backing up file-backed Xen DomU is introduced in this post. This script can be changed to similar platform. In our cluster, virtual machines are stored under /lhome/xen/. Virtual machine with id vmid is stored in directory vmvmid. The raw image disk file name can also be derived from vmid. Some more details
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An I/O Performance Comparison Between loopback Backed and blktap Backed Xen File-backed VBD

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I have done some I/O performance benchmark test of Xen DomU. For easier management, some of our DomU VMs are using file-backed VBDs. Previously, our VMs are using Loopback-mounted file-backed VBDs. But blktap-based support are recommended by Xen community. Before considering changing from loopback based VBD to blktap based VBD, I have done this performance
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How to Duplicate Xen DomU Virtual Machines

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Assumption: There are VBD based Xen DomU virtual machines stored under /home/xen/vm-f11-sample/. There are two files under vm-f11-sample: vm0-f11.run (The configuration file) and vmdisk0 (The virtual disk). Now we want to duplicate the virtual machine vm0 stored under vm-f11-sample to vm-10.0.0.213 which is stored under vm-10.0.0.213. And vm-10.0.0.213’s ip will be 10.0.0.213. The steps to
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A Simple CPU and Memory Performance Test of Xen Dom0 and DomU

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Please refer to Setting Up Xen Dom0 on Fedora : Xen 3.4.1 with Linux Kernel 2.6.29 on Fedora 12 for the platform of this test (this test runs on Fedora 11, however). I have done some simple performance test on DomU and Dom0 and compare with the performance on physical machines. These test are simple,
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The WordPress Desktop Client – lekhonee

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I find a desktop client for publishing to WordPress blogs – lekhonee[1]. I find it interesting and easy to use. This is the first post using it. The interface is simple, but it can provides most of the functions: * Writing post. * Select categories. * Add tags. * Load and Edit the old post.
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Minimizes Thunderbird Windows into the System Tray

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I usually keep Thunderbird open when my computer is open. But Thunderbird is minimized to the taskbar. It will be more convenient if it is minimized or closed to the system tray as an icon.It will be better if it can display the number of unread messages. Mozilla’s software’s addon system give the method to
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Installing NVIDIA Driver in Fedora

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Using rpmfusion’s rpm packages to install NVIDIA driver in Fedora is introduced in this post. First, check the proper drivers for the card on [1]. 1. Add rpmfusion. Enable RPM Fusion repositories 2. Install the driver # yum install kmod-nvidia xorg-x11-drv-nvidia The reboot system. 3. Edit /etc/X11/xorg.conf # nvidia-xconfig The nouveau module conflicts with the
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Create and Manage Virtual Machines on Xen

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In this post, these content are introduced: Create and manage file-backed virtual block device (VBD) for virtual machines on xen. Install Fedora 11 via internet as DomU on top of xen. Manage virtual machines using xm. Create file-backed VBD: The actual space of VBD will be the amount of disk the virtual machine used. And
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Compiling 2.6.29 Kernel Module for VMware Workstation 6.5.2 or VMware Player 2.5.2

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为VMware Workstation 6.5.2 or VMware Player 2.5.2编译2.6.29内核模块 安装好Fedora 11后安装VMware Player 2.5.2时编译内核模块失败。查找了下相关资料,找到如下内容和解决方法。 可能的原因: “The only significant change in fedora 11 comes from gcc, which is more strict about undefined macros, and that sometimes causes vm_check_build to fail.” http://communities.vmware.com/thread/202653 解决方法: 使用一个patch: http://communities.vmware.com/thread/203231

Creating and Running Virtual Machine Using VMware Player and qemu-img

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基于VMware Player, qemu-img创建和运行虚拟机 Linux系统上的免费个人虚拟机方案. 1. 创建虚拟硬盘映象文件: qemu-img create -f vmdk WindowsXPPro.vmdk 10G 2. 创建.vmx虚拟机配置文件: 这是一文本文件. WindowsXPPro.vmx内容: config.version = “8” virtualHW.version = “3” ide0:0.present = “TRUE” ide0:0.filename = “WindowsXPPro.vmdk” memsize = “256” MemAllowAutoScaleDown = “FALSE” ide1:0.present = “TRUE” ide1:0.fileName = “auto detect” ide1:0.deviceType = “cdrom-raw” ide1:0.autodetect = “TRUE” floppy0.present = “FALSE” ethernet0.present = “TRUE” usb.present =
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Moved back to WordPress from MediaWiki

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WordPress is so missed for many great features and plugins. Hence, we moved the site back to the WordPress system on Jul. 12, 2013. MediaWiki is great but, for this site, WordPress is a better solution. The so missed features of WordPress Related posts via the YARPP Plugin. URLs without strongly mapped to the title
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How to Run a cron Job Every Two Weeks / Months / Days

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We may want to run some jobs for every two weeks/months/days… under some situation such as backing up for every other week. In addition, we may add more complex rules for running jobs, e.g. run a command when the load of the server is higher than a certain level. With the help of the shell
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How to Compress/Uncompress Files in Linux Using gzip, bzip2, 7z, rar and zip

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Compress/uncompress files are frequent operations. The normal tools for compressing/uncompressing in Linux is gzip, bzip2, 7z, rar and zip. This post introduces how to compress and uncompress file in Linux using these tools. We use best compressing rate with all these tools and mark the options for “best rate” in bold fonts. We can delete
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Hadoop TeraSort Benchmark

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TeraSort is one of Hadoop’s widely used benchmarks. Hadoop’s distribution contains both the input generator and sorting implementations: the TeraGen generates the input and TeraSort conducts the sorting. Here, we provide a short tutorial for using the Hadoop TeraSort benchmark. TeraGen generates random data that can be used as input data for a subsequent running
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Reading List for Distributed Systems and Cloud Computing

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Understanding the literature is usually the first step to do research, which is the same for systems research on cloud computing. A reading list may help a lot to those that just start in cloud computing research. Prof. Lin Gu, my PhD supervisor, compiled a reading list for system research on cloud computing. The reading
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Setting Up a Git Server Using Gitosis

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Update: Since gitosis is not maintained and supported, please check out gitolite for setting up a new git server. (see the comment from Sitaram Chamarty, the gitolite author, the author of gitolite.) Gitosis is a piece of software writen by Tommi Virtanen for hosting git repositories. It manages multiple repositories under the same user account.
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Hadoop Default Ports

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Hadoop’s namenode and datanodes expose a bunch of TCP ports used by Hadoop’s daemons to communicate to each other or listen directly to users’ requests. These ports information are needed by both the Hadoop users and cluster administrators to write programs or configure firewalls/gateways accordingly. A post written by Philip Zeyliger from Cloudera’s blog summarizes the
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A Simple Sort Benchmark on Hadoop

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After [[hadoop-installation-tutorial|installing Hadoop]], we usually run some benchmark programs to test whether the system works well. In the post of the Hadoop install tutorial, we show a very simple to grep strings from a simple sets of files. In this post, we introduce the Sort for testing and benchmarking Hadoop. The Sort program is also
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