在使用双机软件过程中，如果系统是centos 5.x 默认系统安装完成后为xen内核，那么xen内核引导启动后就会有虚拟网卡（vethx、vif0.x、virbr0、xenbr1等）存在。
这就会直接导致双机软件的两台机器中都会有相同的IP地址存在（virbr0网卡的IP地址都为192.168.122.1）。所以会导致双机系统中的主机关机时，备机不会接管的现象。所以，需要将virbr0卸载掉：
执行命令：yum remove -y libvirt*，用ifconfig -a查看网卡virbr0是否卸载。
如果执行yum报错， 可以vi /etc/yum/plugincon.d/rhnplugin.conf然后将文件中的enable=1改成enable=0，目的是先禁用此功能，再执行yum remove libvirt进行卸载。
重启系统
yum remove NetworkManager –y
设置关闭图形化界面（安装图形化界面，是为了可以应用eclipse，一般应用服务器不会选择安装图形化）
systemctl set-default multi-user.target
chkconfig nfs off chkconfig pcmcia off chkconfig lpd off chkconfig autofs off chkconfig anacron off chkconfig portmap off chkconfig isdn off chkconfig nfslock off chkconfig sendmail off chkconfig cups off chkconfig smartd off chkconfig bluetooth off chkconfig netfs off chkconfig rpcgssd off chkconfig rpcidmapd off chkconfig rpcbind off chkconfig pcscd off chkconfig smolt off chkconfig cups off chkconfig isdn off chkconfig ip6tables off systemctl disable nfs systemctl disable pcmcia systemctl disable lpd systemctl disable autofs systemctl disable anacron systemctl disable portmap systemctl disable isdn systemctl disable nfslock systemctl disable sendmail systemctl disable cups systemctl disable smartd systemctl disable bluetooth systemctl disable netfs systemctl disable rpcgssd systemctl disable rpcidmapd systemctl disable rpcbind systemctl disable pcscd systemctl disable smolt systemctl disable cups systemctl disable isdn systemctl disable ip6tables systemctl disable firewalld
yum -y install gcc yum -y install gcc-c++ yum -y install net-snmp yum -y install ntp yum -y install unzip yum -y install vim-enhanced yum -y install wget yum -y install telnet yum -y install kernel-devel yum -y install finger yum -y install ssh yum -y install nslookup yum -y install zlib-devel yum -y install krb5-devel yum -y install sysstat yum -y install lsof yum -y install fuser yum -y install bind-utils yum -y install glances yum -y install dstat yum -y install net-tools yum -y install vim yum -y install wget
