How to disable the NIC, then the connection is normal ?

[Rick Stevens]

Edward S.P. Leung wrote:
> Rick Stevens wrote:
> 
>> Edward S.P. Leung wrote:
>>
>>> Dear All,
>>>
>>> Mine is Fedora Core 6 :
>>> eth0 ( Internet )
>>> eth1 ( Intranet )
>>>
>>> Now, due to the envoriment problem, the eth1 need to be disable at 
>>> this moment, so I try to do the following config
>>> [root at host1 ~]$ cat /etc/sysconfig/network-scripts/ifcfg-eth1
>>> # Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+
>>> DEVICE=eth1
>>> BROADCAST=192.168.1.255
>>> # HWADDR=00:17:31:7E:F8:34
>>> IPADDR=192.168.1.254
>>> # IPV6ADDR=
>>> # IPV6PREFIX=
>>> NETMASK=255.255.255.0
>>> NETWORK=192.168.1.0
>>> # ONBOOT=yes
>>> ONBOOT=no
>>> [root at host1 ~]$
>>>
>>> After reboot the network function, the server machine can't to 
>>> connect with Internet again :
>>> [root at host1 ~]$ ping -c 3 202.175.xxx.xxx
>>> PING 202.175.xxx.xxx (202.175.xxx.xxx) 56(84) bytes of data.
>>>  From 202.175.xxx.xxx icmp_seq=1 Destination Host Unreachable
>>>  From 202.175.xxx.xxx icmp_seq=2 Destination Host Unreachable
>>>  From 202.175.xxx.xxx icmp_seq=3 Destination Host Unreachable
>>>
>>> So, how must I modify the config of eth1 interface, then the 
>>> connection of Internet will be successful ?
>>
>>
>> Uncomment the "HWADDR=" line to ensure that the configuration ties to
>> the correct NIC.  It's possible that the ifcfg-eth1 setup is really
>> messing with eth0 instead.
>>
>> Second, make sure the default gateway is set up correctly, as your 
>> problem sounds like it's not being set.  If your default gateway is
>> on the network served by the ifcfg-eth1 file above, then it won't be
>> set as you don't have a NIC on that network.  The default gateway is set
>> by a "GATEWAY=" line in one of the ifcfg-eth* files or in the
>> /etc/sysconfig/network file.
>>
>> It'd help if you could post the contents of the following files:
>>
>>     /etc/sysconfig/network-scripts/ifcfg-eth0
>>     /etc/sysconfig/network-scripts/ifcfg-eth1
>>     /etc/sysconfig/network
>>
>> Also the output of the commands "ifcfg eth0" and "ifcfg eth1".  You can
>> obfuscate the actual network addresses if you wish or send the stuff to
>> me off-list and I can try to help you directly.
>> ----------------------------------------------------------------------
>> - Rick Stevens, Systems Engineer                      ricks at nerd.com -
>> - AIM/Skype: therps2        ICQ: 22643734            Yahoo: origrps2 -
>> -                                                                    -
>> -    When you don't know what to do, walk fast and look worried.     -
>> ----------------------------------------------------------------------
>>
> Hello,
> 
> [root at host1 ~]$ cat /etc/sysconfig/network-scripts/ifcfg-eth0
> # VIA Technologies, Inc. VT6102 [Rhine-II]
> DEVICE=eth0
> BROADCAST=202.175.xxx.xxx
> # HWADDR=00:0D:0B:A7:9A:7B
> IPADDR=202.175.xxx.xxx
> # IPV6ADDR=
> # IPV6PREFIX=
> NETMASK=255.255.255.248
> NETWORK=202.175.xxx.xxx
> ONBOOT=yes
> [root at host1 ~]$
> 
> [root at host1 ~]$ cat /etc/sysconfig/network
> NETWORKING=yes
> NETWORKING_IPV6=yes
> HOSTNAME=host1
> GATEWAY=202.175.xxx.xxx
> [root at host1 ~]$
> 
> So, would you mind to give me more suggestion / idea / solution ?

Ok, I don't see anything grotesquely wrong with that so far although
I can't verify the default gateway is on eth0's network.  You defined
a /29 network for it but only gave me the /16 addresses.

Try bringing it up again and run "ifcfg eth0" to verify that it indeed
has an IP address on the 202.175.*.* network.  If it does, then do a
"netstat -rn" and verify you have a default route (denoted by a "G"
under the "FLAGS" column).  If you don't see that, then the gateway
you've defined isn't on eth0's network and we need to look more closely
at your network settings.
----------------------------------------------------------------------
- Rick Stevens, Systems Engineer                      ricks at nerd.com -
- AIM/Skype: therps2        ICQ: 22643734            Yahoo: origrps2 -
-                                                                    -
-              Never eat anything larger than your head              -
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