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Differing IP addresses

I am pinging an address It replies successfully but with an address of I've checked the translation tables but they're all clear, where else shall I look?
Very interesting problem indeed! From my experience I'd say you are dealing with a device on your network that's got two configured IP addresses. If not, then something terribly wrong is happening here!

My suggestion is to check for any routers or possible switches that might be configured with two IP addresses and if you are unable to find anything, grab a network Sniffer and examine the packets running on your network. While you have the Sniffer running on your workstation and performing its 'dirty' work, open a dos prompt and ping the IP address and then the IP address.

When you receive the reply from both ping replies, note down the source MAC Addresses and compare them. If they are the same then the device is configured with two IP addresses, receiving on both, but replying only with one IP address every time. In the case the MAC addresses are different, then you need to track down where the IP address exists. Since I have no information on your network(s) you will need to check for remote networks, firewalls, and other devices, which could be the source of your problem.

This was last published in March 2004

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