Network/Internet connectivity and System Create/Restore from System image

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After I setup a laptop for our network, I created a system image when connected to another laptop; naturally, I used a crossover cable.

The laptop is a Dell Latitude E6530 with Win7 (SP1) and up-to-date, when I imaged it. (BIOS was updated as well)

To test the system image, I re-connected the laptops and used a rescue CD that I had created. It was a beautiful thing; it took me, maybe, a half hour to create and restore the system image. Fast as could be.

I then connected the machine to our network (which has a 192.168.1.xxx addressing scheme) via standard network cable and noticed that I could see the network but couldn’t access the internet. The funny thing is that I could use wireless (which has a 10.1.10.x addressing scheme) and get to the internet (if the network card was disabled, internet access was fine; but not our network, which is as it should be). If the network card/port was enabled, it would clobber the wireless connection.

However, not recalling everything I did to “fix” the problem, but most of it, and listed in no particular order:

[*]ipconfig release/renew
[*]ipconfig flushdns
[*]logged on as different users to test that a particular profile wasn’t corrupted
[*]rebooted the network switch it was connected to (even though I wasn’t having a problem with other PC’s on the same switch)
[*]cussed
[*]connected it to other cables on the same switch (but we have only one switch, so I couldn’t try others)
[*]disabled/enabled both network cards several times, in different order and troubleshooting many of the eventualities with doing things in different order
[*]many reboots

Then I searched the registry for the name of the other laptop and deleted references to it. Rebooted it, and it still had the problem, so I shut it down and went home for the day. This morning, I came in, booted the laptop and things were fine – I could get to the internet and network with the cable plugged in.

So, for testing, I restored the image (without re-creating a second image) from the other laptop. It has worked fine since.

What’s going on? Any other troubleshooting tips for future reference?

Thank you.

Rich

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The cloned machine has inherited the MAC address of the original NIC. You can check this by ipconfig /all or by looking at the event logs.

Your router will attempt to route packets by MAC address not IP address, so when it sees two devices with the same MAC address it cannot route correctly.

Change the MAC address of the clone and update the routing table in the router and it should be OK.

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Tinto Tech,

Good point; I didn’t look at the MAC address previously – however, I did this time around, even though it’s working; the MAC addresses are different. I’ll check that in the future, should this problem re-occur. But, my question is, why is the PC working now and wasn’t working previously?

Any light shed on this matter is appreciated. Thank you.

Rich

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I think it will be difficult to say with certainty why it is working now, but any tweaking of the registry to change or delete the NETBIOS name or other entries could have changed the MAC address and consequently, with the passage of time, updated the ARP cache in the router.

With a new MAC address and a flushed ARP cache it would work.

I’m quite willing to accept that this explanation could turn out be a complete red herring and that there may be another reason, but a cloned MAC address and ARP cache is where I would start.

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Good points again … Thank you for the assistance.

Rich

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