Sharing NICs between laptops

[jeffzimmm]

So, everything is going swimmingly with FOG and my mix of UEFI Dell laptops and their BIOS Dell desktop cousins.

Now I’m running into a complication caused by a cost-saving measure. We only bought 5x Ethernet USB adapters to help me reimage 10 laptops. This means that laptops are sharing NICs, and therefore, MAC addresses.

When I boot from a new laptop using an already-registered NIC, obviously, it’s going to already think it’s registered because the MAC address is the same.

So here’s my query:

1. Is it possible to register all 10 laptops as unique hosts in Fog even though some of them will share Ethernet MAC addresses? Do I use the “Ignore MAC” options on the individual hosts pages?

2. What kinds of mischief will this cause me?

[Wayne Workman]

Depending on how the adapters are used and depending on configuration, this could cause lots of problems, or none at all.

I’m not sure what version of FOG you’re using, I’m assuming some version of FOG Trunk because you’re using UEFI.

There are two “ignore MAC” check-boxes for hosts. But you have 5 adapters. This means any one of those five adapters could be used on any 10 of these laptops. I am fairly sure you don’t want to keep track of which one is used where so… Just add all 5 of these MACs to all 10 laptops in FOG, and check “ignore client” for all 5 USB NICs on all 10 laptops… a lot of work initially, yes, but it SHOULD cause fog to rely on the wifi MAC to image and name. Obviously, you need to add the correct WiFi interface MAC for each of the 10 laptops… not too big of a task.

If you don’t do these things - and image using the adapters, you’ll likely get mis-named computers or even duplicate names on the machines possibly - and this could cause havoc with domain joining and other things that rely on the computer name - all of that is correctable of course, but you should avoid these issues.

With FOG Trunk, I’ve not had any luck with WiFi MAC address staying in the fog db for laptops… seems like every time I image, it has me re-approve the WiFi MAC address… It seems like any MAC that was present before imaging gets deleted during imaging and only the interface used to image is left… The @Developers should chime in on that - and I’d recommend that you watch for that.

Please keep us updated on how this goes for you - because if people don’t tell us, then we don’t know. We are here to help.

[Tom Elliott]

I should add that you should NOT check both the boxes. Add the USB nics as if they are regular hosts, but check the boxes for the “ignore client” so that the FOG Client doesn’t try to do things to that system.

[jeffzimmm]

Fascinating. I wish Dell would print the MAC address on its USB NICs. I’ll start off imaging the first five laptops just to get their NICs registered, then I’ll go into each host and copy-paste the MACs from each NIC.

So, I take it that the WiFi MAC will be the only one that does not have the “Ignore Client” checkbox checked?

[Tom Elliott]

Correct.

[Wayne Workman]

@Tom-Elliott fixed my post. see that’s why I yelled at the devs - because I wasn’t positive.

[jeffzimmm]

UPDATE: Very educational experience for all.

The Fog host database is… sensitive. It would not permit me to add all five NIC MACs to each host, because it does not allow any duplicate MACs anywhere in the database. When you add a MAC to one host which already exists on another, it deletes that MAC from the other host.

So I registered the first 5 laptops, and then added all MACs to Laptop #1. The result was deleting the MACs from Laptops #2-5, which bugged their entries and caused them not to show up in the All Hosts list anymore. I had to manually enter the URL command to delete the host entries for the other laptops.

The better solution, for now, was to manually create the hosts for each of the 1st five laptops, copy-pasting their WiFi MAC address as their primary MACs. Now my 1st five laptops are registered, and none of them have Ethernet NIC MACs at all. This causes their Fog Clients to behave correctly, too–E.g., I can change their hostnames from Fog Management.

This will permit me to register and deploy the remaining 5 laptops using the NICs without problems. It just requires the additional step of changing each one’s MAC to its WiFi and deleting the Ethernet MACs.

[Wayne Workman]

@jeffzimmm So from what I’m gathering - duplicate MACs need to be allowed in the DB. So the “unique” requirement needs removed - and any web code amended to prevent deletion. And - perhaps even a little area added that shows you the hosts with duplicate MACs (just so you can easily see without having to find them via MySQL manually).

@Tom-Elliott , what do you think?