linux下不能上网怎么办?

linux下不能上网怎么办?

我的电脑装了windows xp和redhat ,redhat的网络配置和windows一模一样,但就是上不了网,ping 网关也不通,求助一下!
故障如下:
DEVICE=eth0
BOOTPROTO=none
BROADCAST=172.30.178.255
HWADDR=00:15:F2:BE:50C
IPADDR=172.30.178.165
NETMASK=255.255.255.0
NETWORK=172.30.178.0
ONBOOT=yes
TYPE=Ethernet
USERCTL=no
PEERDNS=no
GATEWAY=172.30.178.254

[root@linux xrgsu]#./xrgsu
Authenticating...
Authenticate SUCCESSFULLY!
Please input 'unauth' to LogOff:
[root@linux xrgsu]# ping 172.30.178.254
PING 172.30.178.254 (172.30.178.254) 56(84) bytes of data.
From 172.30.178.165 icmp_seq=28 Destination Host Unreachable
From 172.30.178.165 icmp_seq=29 Destination Host Unreachable      
你当时在安装的时候,网卡的接入模式是什么模式呢?      
网卡是激活的吧?不成就重启      
问题应该出在本机,网口状态是up 的吗      
From 172.30.178.165 icmp_seq=28 Destination Host Unreachable
从它看出,可能是DNS的问题。