CentOS 6.x 64-bit systems configure Xen virtual machines with third-party yum source installation

What is 1,xen? Xen is a virtual machine system based on the X86 platform that supports common system hardware across multiple operating systems and, more importantly, does not degrade the functionality and performance of the operating system. It can support the virtualization of various operating systems, such as Linux,bsd,windows XP and so on.

2, why use Xen? Xen wants to be able to run up to 100 virtual machines (VMS) at the same time on a single server. In addition, Xen has several of the following features. Xen is the fastest and most secure virtual machine system, an open source system that has been supported by many of the world's leading companies. One more thing, it's free. The performance of Xen has improved significantly compared to several existing virtual machine systems, such as VMWARE,UML (User-mode Linux). In addition, Xen provides comprehensive support for hardware virtualization technologies. For example, Intel's new generation of Vt-x processors supports CPU,MMU and memory virtualization. AMD's Pacifica also have similar technologies. For such hardware, Xen can be managed without modifying the Guestos directly.

3, the purpose of virtualization technology: The initial need for virtualization is to reduce resource costs and integrate multiple operating systems. The concept of OS virtualization appeared in the 1972 IBM System 360. Simply put, a system management layer is inserted between the OS and the hardware, and the system management is responsible for scheduling hardware usage between multiple OSes, including MMU,I/O,DMA and so on. In today's IT systems, virtualization is becoming a key technology area. The main reasons are the following points. Cost savings currently in most server applications, only 15% of the server's own hardware capacity can be used. But in order to expand different businesses, users also need to acquire new servers. According to statistics, a server in the data center costs $10,000 per year, plus the cost of system maintenance, management, license of hardware and software, and so on. With virtualization technology in use, you can run multiple operating systems and applications at the same time on each server. Efficient use of the capabilities of the server hardware itself. This reduces the cost of system acquisition and maintenance of the entire life cycle. Improve the system distribution and management capabilities using virtualization, you can easily implement the dynamic distribution of the OS. Patch installation, constant power system maintenance, etc. can also be achieved. The high-reliability implementation isolates the hardware from the OS, and the physical devices used in the OS become logical devices. Improve the reliability of the system. In addition, for the virtualized system, the backup and recovery of the OS is very easy to implement, once a system failure can be quickly restored.

4, the difference between full and semi-defocus: The difference between PV (para-vritralization) and FV (Full-vritralization), mainly based on the hardware emulation degree of guest OS. Semi-virtual technology is not fully hardware simulation, its performance is slightly higher than the full-virtualization technology, semi-virtualization does not require CPU support VT technology. Full virtualization technology full hardware emulation, but must CPU support VT Technology 1) How to determine whether the CPU supports VT technology? Under the Linux platform, enter grep ' (VMX|SVM) ' –color=always/proc/cpuinfo to see VMX or smx in the print message, VMX is inter CPU virtualization, and SMX is AMD's CPU virtualization.
If you have Xen installed, you cannot see the two tags by entering the command above. Command: XM DMESG | Grep-i HVM
If not, there is also the possibility that the CPU full virtual function is not turned on in the BIOS. 2) Full and semi-virtualized operating systems supported: Semi-virtualization does not support installation of Windows clients.
Under CentOS 5, we can install Xen directly from Yum, but not at CentOS 6. The reason is that Redhat has KVM as the default virtualization technology solution. So if you need to deploy Xen under RHEL6, you will have to build your own Xen-supported Pvops kernel and the latest version. Compiling and installing the custom Pvops kernel and Xen are important in the production environment, which maximizes system performance and guarantees stability, but is relatively complex and not suitable for beginners.
This article describes the method of installing Xen from a third-party source under CentOS 6 (RHEL6). The installation comes with a pvops kernel that users do not have to compile themselves. However, in the production environment, it is recommended to compile the installation method to facilitate the tuning of the kernel.
Before installing, make sure your CPU supports vt-d and open vt-d support in the BIOS (this option is off by default). For more information on hardware such as CPUs and motherboards that support vt-d, refer to VTD HowTo on the Xen wiki.

First step: Minimize the installation of CentOS 6 64bit (skip)
System installation is not much said, basically everyone will, according to their preferences installed on OK. If you have questions, you can refer to RHEL6 Xen4 Tutorial on the Xen wiki.
After the system installation is complete, the following actions are required:
1.1 Updating the system
# Yum Update

1.2 Disabling SELinux
# Vim/etc/selinux/config
Change the value of SELINUX to: selinux=disabled.
# reboot

Step Two: Install Bridge-utils
Yum Install Bridge-utils

Step three: Use a third-party source
Yum Install http://au1.mirror.crc.id.au/repo/el6/x86_64/kernel-xen-release-6-5.noarch.rpm

Fourth step: Yum installs the Pvops kernel and Xen
Yum Install Kernel-xen Xen

Fifth Step: Modify Gurb Boot options
Vi/etc/grub.conf
Title Scientific Linux (2.6.32-4.el6xen.x86_64)
Root (hd0,0)
kernel/xen.gz dom0_mem=1024m Cpufreq=xen Dom0_max_vcpus=1 dom0_vcpus_pin
module/vmlinuz-2.6.32-4.el6xen.x86_64 ro root=/dev/mapper/raid1-xenhost rd_lvm_lv=raid1/xenhost rd_MD_UUID= Afb92c19:b9b1e3ae:07af315d:738e38be Rd_no_luks rd_no_dm Lang=en_us. UTF-8 Sysfont=latarcyrheb-sun16 keyboardtype=pc keytable=us Crashkernel=auto
Module/initramfs-2.6.32-4.el6xen.x86_64.img

Sixth step: Turn off SELinux/empty IPTables rules
Vi/etc/sysconfig/selinux
# This file controls the state of the SELinux on the system.
# selinux= can take one of these three values:
# Enforcing-selinux security policy is enforced.
# Permissive-selinux Prints warnings instead of enforcing.
# disabled-no SELinux policy is loaded.
Selinux=disabled
# selinuxtype= can take one of these the values:
# targeted-targeted processes is protected,
# Mls-multi level Security protection.
selinuxtype=targeted
echo "" >/etc/sysconfig/iptables

Seventh Step: Restart


For more information, please contact Ding Feng Hu Jiashong
qq.2881064155
skype.live:2881064155

CentOS 6.x 64-bit systems configure Xen virtual machines with third-party yum source installations