Setup your cloud server in 3 minutes with Xen 4.1 on Ubuntu 11.10

Ubuntu support xen officially since 11.10. It is really easy to install the packages. Although some issues should be fixed manually, it is a painless experience. Here’s the steps to setup your cloud server in 3 minutes with Xen 4.1 on Ubuntu 11.10.

1. Install xen hypervisor and utilities
sudo apt-get install xen-hypervisor-4.1-amd64 xen-utils-4.1 xenwatch xen-tools xen-utils-common xenstore-utils

sudo apt-get install virtinst virt-viewer virt-manager

2. Restart os, choose the xen kernel， verify xen installation
# xm info
# brctl show

3. Config your xend 
$ sudo vim /etc/xen/xend-config.sxp

comment out (xend-unix-server yes) at the file, that means make sure the following line exists or been added :
(xend-unix-server yes)

#vi ~/.bashrc , add the following line:

1	export VIRSH_DEFAULT_CONNECT_URI="xen:///"

4. Restart, choose the xen kernel， and verify libvirt

# virsh version

Compiled against library: libvir 0.8.3
Using library: libvir 0.8.3
Using API: Xen 3.0.1
Running hypervisor: Xen 4.0.0

Conguratulations, all packages installed successfully.

5. Run virtual machine manager to manage your vms.

# virt-manager

Then you will see the screen virtual machine manager screen:

Create virtual machine in virt-manager,

error occur when finish creation, and show something like:
if ret is None:raise libvirtError(‘virDomainCreateLinux() failed’, conn=self)
….
/usr/lib64/xen/bin/qemu-dm: ….

that means qemu-dm could not be found, try to fix it:

#mkdir /usr/lib64/xen -p
#cp /usr/lib/xen-4.1/* -r /usr/lib64/xen/

then continue to finish creation of the virtual machine, still error occured, and show something like:
libvirtError: POST operation failed: xend_post: error from xen daemon: (xend.err …
or something like this:

libvirtError: POST操作失败: xend_post：来自 xen 守护进程的错误：

check the error log,  it will give you some clues:
# less /var/log/xen/xend.log

the log shows error occured and logged at /var/log/xen/qemu-dm-demo.log, check it:
# less /var/log/xen/qemu-dm-demo.log

it says /usr/share/qemu/keymaps/en-us could not be found, the keymaps really does not exist in my disk.
and find it at /usr/share by :
#ls /usr/share/qemu (and press Tab, it shows qemu-linaro exist)

so just copy it to fix:
#cp -r /usr/share/qemu-linaro/ /usr/share/qemu

then continue to finish the vm creation. Wow, it works!