After clone Redhat machine by using vSphere, can't reach the new machine

本文介绍了解决通过vSphere克隆RedHat机器后出现的网络配置问题的方法。详细步骤包括克隆机器、配置IP地址、设置默认网关等，最终使克隆机能够访问外部网络。

After cloning the redhat machine by using vSphere and configure the ip address by using ifconfig, the new machine is not accessible by public network, but can be accessible in the intranet of the VM cluster.

1) Clone the redhat machine by using vSphere without customization.

2) Config the ip address for the new redhat machine.
/sbin/ifconfig eth0 10.5.6.36 netmask 255.255.255.0 broadcast 10.5.6.255

3) IP addr 10.5.6.36 can't be accessible through outer network, but can be pinged in the intranet of the VM cluster. And on this new machine, can't ping outer network. It reports
"connect: Network is unreachable"

4) List the router. It obviously has problem, it should have a default gateway out.
[root@lpgpdev ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
10.5.6.0 * 255.255.255.0 U 0 0 0 eth0

5) Adding the default gateway out.
[root@lpgpdev ~]# route add -net default gw 10.5.6.1 dev eth0
[root@lpgpdev ~]# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.5.6.0        *               255.255.255.0   U     0      0        0 eth0
default         10.5.6.1        0.0.0.0         UG    0      0        0 eth0

6) Everything is good now ! The new machine can ping outer network and outer network can ping it.