Fedora’s font rendering isn’t very nice. At least on my laptop with Fedora 12. Bytecode Interpreter (BCI for short) is disabled by default because of patent issues. As the TrueType bytecode patents have expired. We may enable BCI in Fedora now. TrueType announced that BCI is enabled by default from 2.4. Fedora 12’s TrueType version…
The is a simple introduction to paravirt_ops in Linux kernel for Xen, VMware, etc. We make this introduction from the view of code. We use the function raw_local_irq_disable() and raw_local_irq_enable() functions in Linux kernel to introduce paravirt_ops for Xen and Xenified kernel. Please download the introduction to paravirt_ops pdf file: introduction-to-pv-ops-v3.pdf
This is a introduction to *nix’s process management tools: pkill and pgrep. As this site’s domain name was pkill.info, a introduction to pkill should exist here. NAME pgrep, pkill – look up or signal processes based on name and other attributes SYNOPSIS pgrep [-flvx] [-d delimiter] [-n|-o] [-P ppid,…] [-g pgrp,…] [-s sid,…] [-u euid,…]…
It is common to connect servers with only internal IPs from several clusters. VPN is a common technique for this. With iptables, we can implement many functions of VPN with possibly higher performance. The slides here give a brief introduction to how to set up a VPN-like network between 2 clusters which connect to each…
How to create a LVM group from two hard disk partitions is introduced in this post. Assume we have installed two hard disks /dev/sdb and /dev/sdc to the server, our task now is to create one LVM volume group vg_xen for installing LVM backed Xen DomUs from these two disks. We will do this by…
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…
The Xen hypervisor is a powerful virtualization solution that provides virtualization capabilities for x86, x86-64, and ARM architectures. The source code structure of Xen is organized into several directories, each of which contains a specific set of files. The backend and frontend drivers are an important part of the Xen hypervisor, and they provide a…
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 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. Creating LVM-backed Xen DomU is introduced in this post. Create LVM-backed VBD Suppose we have a LVM volume…
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…
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]]…
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…
There are funny Gnome easter eggs. One is “free the fish”, and another one is “gegls from outer space”. “free the fish” in Gnome 2 Press Alt+F2 to open “Run Application” dialog Enter “free the fish” Hit Enter “geglx from outer space” in Gnome 2 Press Alt+F2 to open “Run Application” dialog Enter “gegls from…
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…
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…
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….
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…
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…
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…