Duplicating and Backing Up LVM Backed Xen DomU from a Remote Server

Posted on

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
Read more

Linux Cluster Solutions

Posted on

Solutions to Linux cluster construction and management such as unified account management, NFS home directory, network configurations are summarised in this post. The post is keeping updating while new solutions is added to this site. ===Account and storage management=== [[unified-linux-login-and-home-directory-using-openldap-and-nfsautomount|Unified Linux Login and Home Directory Using OpenLDAP and NFS/automount]] [[backup-linux-home-directory-using-rsync|Backup Linux Home Directory Using rsync]]
Read more

Xen DomU’s I/O Performance of LVM and loopback Backed VBDs

Posted on

This posts list benchmark (using bonnie++) result of I/O performance of Xen LVM and loopback backed VBDs. The configuration of machines Dom0 VCPU: 2 (Intel(R) Xeon(R) CPU E5520  @ 2.27GHz) Memory: 2GB Xen and Linux kernel: Xen 3.4.3 with Xenified 2.6.32.13 kernel DomU VCPU: 2 Memory: 2GB Linux kernel: Fedora (2.6.32.19-163.fc12.x86_64) DomU’s profile: name=”10.0.1.200″ vcps=2
Read more

Setting up Stable Xen Dom0 with Fedora: Xen 3.4.3 with Xenified Linux Kernel 2.6.32.13 in Fedora 12

Posted on

This is the latest stable and recommended stable Xen Dom0 solution on Fedora 12. No serious bug found till now and we will fix the bugs by ourselves if some appears. It also works on Fedora 14 as well. It should not be hard to use this solution on other versions of Fedora or other
Read more

Problems during Installing Xen Dom0 in Fedora

Posted on

Here is a list of problem that may occur during installing and configuring Xen Dom0 in Fedora. It is found originally in Fedora systems, but the tips in this post should also be helpful for installing Xen Dom0 on other platforms. BIOS configuration If xen stops at: “I/O virtualization disabled.” We may need to enable
Read more

Set up and Run Linux Xen Dom0 and DomU VMs

Posted on

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.
Read more

Finding out Linux Network Configuration Information

Posted on

There is various network configuration information in Linux and lots tools can be used to find out those configuration information. Finding out these network information in Fedora Linux as the example will be introduced. IP address, MAC address and netmask ifconfig will print out all the network interfaces and their information including the IP address
Read more

Setting Up Xen DomU on Fedora Linux (Fedora 12)

Posted on

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
Read more

Configuring Mouse Cursor Style for GTK Applications in KDE Desktop

Posted on

Update on Jan. 7, 2012: The package for the gtk application style setting on KDE 4.7 is kcm-gtk. The command to install this package is: “# yum install kcm-gtk”. One annoying thing when using KDE desktop is that the theme and style of GTK applications differ from KDE’s. The gtk-qt-engine can let us select the
Read more

NVIDIA Driver in Linux not Displaying Logo During Booting

Posted on

The NVIDIA video card driver in Linux will display the NVIDIA logo by default during booting the X server after we successfully installed the driver. If we don’t like to see the logo every time we start X server, we can disable it. We need to edit the Xorg configuration file /etc/X11/xorg.conf with root permission.
Read more

How to Set Date, Time and Timezone in Linux

Posted on

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
Read more

Making dnf/yum Not Update Certain Packages

Posted on

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
Read more

Gnome2 Style: Shiki Colors+Gnome Colors

Posted on

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 ->
Read more

Setting Up Xen Dom0 on Fedora : Xen 3.4.1 with Linux Kernel 2.6.29 on Fedora 12

Posted on

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
Read more

Speeding Up Firefox in Linux

Posted on

Firefox can be much faster on Linux! Let’s speed up Firefox on Linux system. Part 1 and 2 only config firefox, so it can also be used on other platform such as Windows. 1. Pipe-lining network connection Most of us use a broad band width network, then why not pip line the connection from Firefox?
Read more

Sending Email Using mailx/s-nail in Linux Through Gmail SMTP

Posted on

The heirloom mailx (or s-nail if you are using Ubuntu 18 or later or similar releases) command in Linux is still providing service for guys like me, especially when we need to send email automatically by script. Gmail is great. Now, how to use gmail’s smtp in mailx/mail? gmail is a little special since gmail’s
Read more

Setting Up Linux Network Gateway Using iptables and route

Posted on

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
Read more

How to Control or Disable SELinux in Fedora and CentOS Linux

Posted on

For most of cases, you should not disable SELinux. However, for some users, SELinux may cause problems or is not needed. We may just make it not block operations or totally disable it. Making SELinux log warnings instead of blocking For many cases, people find SELinux blocks operations. For tests or some other situations, you
Read more

Unified Xen DomU configuration file

Posted on

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
Read more

Automatically Backing Up Xen File-backed DomU

Posted on

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
Read more