LVM’s snapshot feature enables us to duplicate an LVM backed Xen DomU in seconds rather than minutes. We no longer need to copy the entire file system image like backing up file backed Xen DomU. We just need to make a snapshot of the current Xen DomU in seconds. When there are changes to the…
LVM’s snapshot feature enables us to duplicate an LVM backed Xen DomU in seconds inside of the same volume group. When we want to duplicate LVM backed Xen DomU from a remote server, we need to make use of LVM’s snapshot function and tools like scp and dd. Backing up the DomU is only part…
In Linux, it is often necessary to check the firmware version of your system. The firmware, also known as BIOS (Basic Input/Output System), is a software that is built into the hardware of your system and serves as an interface between the hardware and the operating system. In this post, we will explore how to…
How to create a Fedora live USB media is introduced in this post. We can boot to Fedora operating system environment through a live USB system in the USB flash media on a USB-bootable computer without writing the computer’s hard disk. We can also install Fedora operating system from the live system environment. Remember to…
The Xen solutions including installing and configuring Dom0 and DomU are summarized here. LVM volumes as backing for DomU’s file system is an appealing solution to Xen VBD. LVM volumes can dynamically grow/shrink and snapshot. These features make it simple and fast to duplicate DomU and adding storage to DomU. LVM backed DomU is recommended….
We may need to install some old packages such as the kernel in our Linux box. Let’s use installing a older version of Linux kernel in Fedora as the example to introduce how to install old packages from the repository using yum. By now, suppose we have install kernel-2.6.32.16-143 in the Linux box and we…
Creating file-backed virtual block device (VBD) for Xen virtual machines and installing Fedora 12 in Xen DomU via internet will be introduced. Note that this tutorial is based on a pretty old OS (Fedora 12). But the method here is still valid while some minor details may need to be changed for latest Xen and…
How to jailbreak Apple iPod touch in Linux will be introduced in this article. We use Spirit to jailbreak iPod touch. Spirit[1] is an untethered jailbreak for iPad, iPhone, and iPod touch on certain firmware versions. Please read [1] for requirement when using Spirit. Currently, the version of iTunes used should be iTune 9 earlier…
How to set date, time and timezone on Linux/Unix box will be introduced in this post. Unix time, or POSIX time which is a system for describing points in time is the number of seconds elapsed since midnight UTC on the morning of January 1, 1970, not counting leap seconds. The number of seconds elapsed…
We may not want to update some packages such the kernel on a stable server while updating the system. If we run “dnf update” or “yum update”, we may get suggested by dnf/yum to install all the packages with updates. In this post, how to make dnf/yum not update certain packages such the kernel when…
Linux port forwarding is simple to do with iptables which may probably already being used as the firewall or part of the setting up a Linux gateway. In the Linux kernel, port forwarding is achieved by packet filter rules in iptables. Port forwarding Port forwarding also called “port mapping” commonly refers to the network address…
tmpfs has blazing speed. Why not set up a high speed NFS server on top of tmpfs? A little trick is required for setting NFS server on top of /dev/shm. If we add a normal entry in /etc/export and them run # exportfs -a exportfs will give us a warning like this: exportfs: Warning: /dev/shm…
How to set up eCryptFS in Linux will be introduced in this post. We can store encrypted files in one eCryptFS directory, the manual way. The content can be seen only after it is mounted as eCryptFS file system. Otherwise, the users can only see garbled characters in the files. Note that this tutorial will…
I believe many users are using pidgin and google apps. Google apps support Google Talk. Can we use it in Pidgin? The answer is yes. How to use Google apps account for Google Talk in Pidgin will be introduced in this post. Let’s use one email address as the example: eric @ example.com First add…
Please refer to for the latest stable Xen Dom0 solution. In this post, the detailed tutorial for setting up Xen 3.4.1 dom0 on top of Fedora 12 with kernel 2.6.29 will be introduced. Hardware: Dom0 hardware platform: Motherboard: INTEL S5500BC S5500 Quad Core Xeon Server Board CPU: 2 x Intel Quad Core Xeon E5520 2.26G…
How to query installed files from a package and query which package one installed file is in will be introduced. Query installed files from a package $ rpm -ql package_name Query which package a installed file is in $ rpm -qf /full/path/to/installed/file
I need to backup my Linux home directory to one of my portable hard disk. I tried to use git, but failed since git doesn’t support large file (I failed after many tries, I have file larger than 5G). I find rsync, the fast, versatile, remote (and local) file-copying tool and I am happy with…
The Linux Gnome style that I like is Shiki-color + Gnome colors icon theme. It looks pretty and professional and it is fast. How to install them: Gtk engine: # yum install gtk-murrine-engine Icon theme: # yum install gnome-colors-icon-theme Theme: Dowload from here: http://gnome-look.org/content/show.php/Shiki-Colors?content=86717 Install it by Appearance Preference -> Install. Configuration: Appearance Preference ->…
ffmpeg is a powerful tool and it can do the work of capturing Linux desktop video very well. ffmpeg is a very fast video and audio converter that can also grab from a live audio/video source. ffmpeg can grab X11 input and create a video file such as mp4 at specific fps with the specific…
Automatic passwrod-less ssh login can make our life easier. To enable this, we have 2 options: using key-based authentication by copying our SSH public keys to the remote machines for automatic password-less login or using password-based authentication. I will introduce the 2 options in the post. Before you start, please note that key-based authentication is…