Port1 vs Port2 and duplicate Mac entries in JSS

[donmontalvo]

So I noticed today that if a user switches his/her Ethernet cable from Port1 to Port2 on their Mac Pro, the computer shows up in JSS.

Is the MAC Address the only criteria used by JSS to vet out duplicates? Is there a way for JSS to know, perhaps based on serial number, that a computer is already in JSS?

What about laptops that switch between Ethernet and Wifi...(we don't have many)...do they run the risk of showing up twice in JSS too?

Don

[donmontalvo · Accepted solution]

OK, with JAMF Support's help, we think we may have found the culprit to these duplicate Macs in JSS. A quick check of the network interfaces shows one Mac Pro in JSS, duplicated with these ethernet interfaces:

en0 00:1f:5b:f0:9b:de <-- shows up in JSS en1 00:1e:c2:a9:91:92 vnic0 00:1c:42:00:00:08 <-- shows up in JSS

Turns out vinc0 is related to Parallels:

http://download.parallels.com/doc/psbm/en/Parallels_Server_Bare_Metal_Users_Guide/29258.htm

JAMF are investigating...

Don

[donmontalvo]

Of course I meant:

"the computer shows up *TWICE* in JSS."

Not. Enough. Coffee. :)

Don

[mark_sampers]

Don,

In response to:

What about laptops that switch between Ethernet and Wifi...(we don't have
many)...do they run the risk of showing up twice in JSS too?

We save several schools with teacher MacBooks. They connect via ethernet
and/or Wi-Fi. They only appear once in our JSS. The IP listed in inventory
is the last IP used when reporting into the JSS so the IP does change.

-- Mark Sampers
Technology Support Cluster Specialist
Independent School District 196
Rosemount-Apple Valley-Eagan Public Schools
3455 153rd Street West
Rosemount, MN 55068
651-423-7973

[Walter]

My MacBook Pro switches between wifi and hardwired. It only shows up once in the JSS. The JSS may allow for wi-fi vs wired movement, but perhaps not for movement between multiple wired ports.
--
Walter Rowe, System Hosting
Enterprise Systems / OISM
walter.rowe at nist.gov<mailto:walter.rowe at nist.gov>
301-975-2885

[sean]

Don,

I configure our network locations, such that only one port can be active at a time. None of our locations allow for the 2nd network port and our dhcp/mac address config file just allows for port 1 only, so port 2 can't and is never used.

Sean

[donmontalvo]

Hi Mark,

Interesting, seems like it's only a problem with Mac Pro desktop computers with dual Ethernet ports.

On those laptops, is Ethernet=en0 and Wi-Fi=en1?

We are on 7.31 (hope to move to 8.x over the holidays), so we still have the JSS Setup Utility to run database checks on.

Don

[bentoms]

Don,

I've never seen the issue.

I thought the JSS created it's objects using serial number... Better ask support.

Regards,

Ben.

[donmontalvo]

Tested in our LAB environment, but could not reproduce. LAB has Lion Server (also 10.7.2) running JSS 8.31, and Lion (also 10.7.2) Mac Pro client doesn't have this problem.

So I'll confirm in the live environment which is JSS 7.31 and server/client is Snow Leopard.

Thanks,
Don

[donmontalvo · Accepted solution]

OK, with JAMF Support's help, we think we may have found the culprit to these duplicate Macs in JSS. A quick check of the network interfaces shows one Mac Pro in JSS, duplicated with these ethernet interfaces:

en0 00:1f:5b:f0:9b:de <-- shows up in JSS en1 00:1e:c2:a9:91:92 vnic0 00:1c:42:00:00:08 <-- shows up in JSS

Turns out vinc0 is related to Parallels:

http://download.parallels.com/doc/psbm/en/Parallels_Server_Bare_Metal_Users_Guide/29258.htm

JAMF are investigating...

Don

[rob_potvin · Accepted solution]

Couldn't you add the the mac address from the vnic0 to your removable MAC addresses list in inventory options?

[donmontalvo]

Couldn't you add the the mac address from the vnic0 to your removable MAC addresses list in inventory options?

Yep, we're doing that...but it's a reactive (vs proactive) measure...and it doesn't stop real duplicates from showing up. For example if you dual-boot a Mac, the Mac shows up twice in JSS....

https://jamfnation.jamfsoftware.com/discussion.html?id=1060

Don