Strange network connectivity problem

Posted by Marc on Server Fault See other posts from Server Fault or by Marc
Published on 2010-03-26T05:15:43Z Indexed on 2010/03/26 5:23 UTC
Read the original article Hit count: 229

Filed under:

ping

|

network

Here is my network connectivity:

cable modem
     |
     |(WAN)
  wrt54g (default gateway, 192.168.1.1) -- earth
     |(LAN)
     |
Simple Switch1
|          |
|          |
|      SimpleSwitch2- neptune      
|        |      |   
|      mars  mercury
| 
|- venus  
| 
|- laptop
|
saturn (Windows AD DC)

simpleSwitch2 was hanging off the wrt54g. I moved it to SW1 during troubleshooting. Nothing described below was any different.

earth is connected via wireless to the wrt54g.

I can ping from laptop to mars, neptune & mercury. I can ping from earth to venus, saturn & laptop.

However, pinging mars, mercury or neptune from earth gives the following result.

Pinging mars.XXX.XXX [192.168.1.105] with 32 bytes of data:
Reply from 192.168.1.122: Destination host unreachable.
Reply from 192.168.1.122: Destination host unreachable.
Reply from 192.168.1.122: Destination host unreachable.
Reply from 192.168.1.122: Destination host unreachable.

Ping statistics for 192.168.1.105:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

.122 is the address of the machine from which I am pinging.

earth is a Vista machine. Windows firewall is off.

saturn is my DNS & DHCP server.

Can anyone give me any ideas what the h*ll is going on? Clearly the topology is a factor

And yes, I am a space geek.

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