Xen使用console进入hvm虚拟机

HVM虚拟机默认不支持 xl console，需要使用图形界面安装好虚拟机后修改一些配置文件，让其支持xm/xl console 的连接方式。

1. 在Dom0修改虚拟机的配置文件，添加：

serial='pty'

2. 修改虚拟机内部的 /boot/grub/menu.lst 或者 /boot/grub/grub.conf 文件，添加：

serial --unit=0 --speed=9600
terminal --timeout=5 serial console

和：

console=ttyS0

如下所示：

[root@localhost ~]# cat /etc/grub.conf 
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/mapper/VolGroup-lv_root
#          initrd /initrd-[generic-]version.img
#boot=/dev/xvda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS 6 (2.6.32-754.el6.x86_64)
	root (hd0,0)
	kernel /vmlinuz-2.6.32-754.el6.x86_64 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup/lv_root  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet console=ttyS0
	initrd /initramfs-2.6.32-754.el6.x86_64.img
	serial --unit=0 --speed=9600
	terminal --timeout=5 serial console