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New Member

Strange connectivity issue...

I have what I think are strange results via ping.

From a machine I can ping a certain address.

From the machines gateway router I cannot ping that same address. Any ideas or theories?????Thanks

6 REPLIES
New Member

Re: Strange connectivity issue...

Are the machines on the same subnet, or does the ping have to travel through the gateway in order to reach its destination?

New Member

Re: Strange connectivity issue...

The machines are on different subs. Here is the whole scheme.

Machine1

ip: 199.195.107.45

sub: 255.255.255.0

gateway: 199.195.107.1

Machine 2

ip: 173.7.7.253

sub: 255.255.0.0

gateway 173.7.7.1

Machine 1 can ping machine 2

When I am on my router which is machine 1's gateway

I cannot ping machine 2.

New Member

Re: Strange connectivity issue...

Try and extended ping from machine 1's gateway using 199.195.107.1 as your source. If that works find out what interface that router uses to get to machine 2 and veryify machine 2's gateway router has that route.

New Member

Re: Strange connectivity issue...

The extended ping works. I do not understand why it would be a route table issue if I can ping the machine and his gateway cannot? If it was a route issue would'nt the machine have the same problem...Thanks

New Member

Re: Strange connectivity issue...

When you ping from the machine it grabs its interface IP as the source but when you ping from the router it grabs the outgoing interfaces IP as the source.

New Member

Re: Strange connectivity issue...

I'd check to make sure the router and the workstation are ARPing each other correctly. Also, make sure you have no wierd access lists set up that could be getting in the way. Have you tried other workstations on both sides to verify your symptoms? Is there another router that you can try the same test on? Can the router ping ANYTHING else on the subnet? How about reversing machines? You could do a CLEAR IP ARP to clear the ARP table and let it discover the workstation again.

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