RE: A PC with two NIC routing problem

And tcpdump on Linux. You can see there clearly if ICMP packets are received
and where replies are sent.
 
-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Mahaffey, Brian
Sent: 1-Oct-10 14:31
To: Jack; ccielab_at_groupstudy.com
Subject: RE: A PC with two NIC routing problem

Debug ip packet and start your tests that will tell you your issue.

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Jack
Sent: Friday, October 01, 2010 11:05 AM
To: ccielab_at_groupstudy.com
Subject: Re: A PC with two NIC routing problem

Here is my guess:
when host10 pings 11.11.11.100, the ip packet source address is
10.10.10.10 and it reaches 11.11.11.100;
when the linux PC sends the reply, it uses 10.10.10.100 as the source
address and Host10 does not like it because it is not from 11.11.11.100.
Does it make sense?
If so, how to fix it?

Thanks,
Jack

On 10/01/2010 01:41 PM, Sergey Matashuk wrote:
> do host10 and host11 have defult gateway configured?
>
> On Fri, Oct 1, 2010 at 8:32 PM, Jack<ccie.unnumbered_at_gmail.com>
wrote:
>
>> A linux PC has two NIC cards:
>> eth0=10.10.10.100/24 belongs to VLAN 10
>> eth1=11.11.11.100/24 belongs to VLAN 11
>> the default gateway is 10.10.10.1
>>
>> A layer 3 switch has the following configuration:
>> int vlan 10
>> ip addr 10.10.10.1 255.255.255.0
>> int vlan 11
>> ip addr 11.11.11.1 255.255.255.0
>>
>>
>> Host10 on vlan 10 with ip address 10.10.10.10/24 can ping
10.10.10.100, but
>> cannot ping 11.11.11.100
>>
>> Host11 on vlan 11 with ip address 11.11.11.11/24 can ping
11.11.11.100, but
>> cannot ping 10.10.10.100
>>
>>
>> How to make the linux PC respond to all pings from both hosts?
>>
>>
>> Thanks,
>> Jack
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>>
Received on Fri Oct 01 2010 - 14:53:32 ART