How To Set Macaddr With Nmcli

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I see my problem.  I mis-read what

nmcli con mod eth0 mac “02:67:15:00:81:0B”

does.  It sets HWADDR; which interface to link to, not MACADDR, what MAC
address you want for your interface.

So I have read the nmcli pages and googled a bit.  I cannot find a way to set MACADDR.  I suppose I can set HWADDR then use sed to change it to MACADDR, but this seems a real hack.

ARM boards do not have assigned MAC addresses.  Uboot uses various information to generate a local MAC address.  I want finer control of my MAC address for my servers.  In the past, I just edited ifcfg-eth0.  I
am trying now to do it all with nmcli.  I thought I had it, but I
misread the manual.

Any pointers?

thanks

BTW, I remember setting MAC addresses on 3COM 3C501C boards because the old board died and we had software licensed to specific MAC addresses. 
So you had to specify your MAC address in the config file.  The DEC
admin had to do a similar thing if he had to swap out his LAN card
(related: read up on why Dr. Comer set ARP timeout to 10min).

Then there was that counterfeit 3C503C from Malaysia, all with the same MAC address.  Caused havoc on the networks.  EVERYONE had to specify their MAC address with those.  3COM did find the plant making these clones and shut them down.  But the damage was done to a lot of us.

3 thoughts on - How To Set Macaddr With Nmcli

  • I see my problem.  I mis-read what

    nmcli con mod eth0 mac “02:67:15:00:81:0B”

    does.  It sets HWADDR; which interface to link to, not MACADDR, what MAC
    address you want for your interface.

    So I have read the nmcli pages and googled a bit.  I cannot find a way to set MACADDR.  I suppose I can set HWADDR then use sed to change it to MACADDR, but this seems a real hack.

    ARM boards do not have assigned MAC addresses.  Uboot uses various information to generate a local MAC address.  I want finer control of my MAC address for my servers.  In the past, I just edited ifcfg-eth0.  I
    am trying now to do it all with nmcli.  I thought I had it, but I
    misread the manual.

    Any pointers?

    thanks

    BTW, I remember setting MAC addresses on 3COM 3C501C boards because the old board died and we had software licensed to specific MAC addresses. 
    So you had to specify your MAC address in the config file.  The DEC
    admin had to do a similar thing if he had to swap out his LAN card
    (related: read up on why Dr. Comer set ARP timeout to 10min).

    Then there was that counterfeit 3C503C from Malaysia, all with the same MAC address.  Caused havoc on the networks.  EVERYONE had to specify their MAC address with those.  3COM did find the plant making these clones and shut them down.  But the damage was done to a lot of us.

  • Robert Moskowitz wrote:
    that’s all I’ve changed.

    I have to spoof it on a couple of users’ workstations, because they’re running 9 yr old software that’s productive… and tied to the MAC address
    *and* to the NIC name, so I have to have a couple of parms on the grub2
    command line, because it *has* to be named eth0. Oh, and the maker was sold, and the new company says, “you changed machines? Sure, we’ll generate a new license… that’ll be $15,000, please.

    Oh, wow, I don’t remember hearing about that. What a freakin’ pain!

    mark

  • Yo, Mark

    I don’t need the udev/rules.  C7-armv7 is working just fine with eth0.

    But I want to script it for my howto using nmcli.  I cannot see how to set MACADDR with nmcli.  I may have to join their list to ask. Nicely.

    Yeah, what he said.  Been there.

    I knew the 3COM engineer that figured it out.  The boards were perfect clones.  But all with the same MAC address.  Packaging was perfect.  He put one of the boxes in water until it came apart, got someone to read the newspapers the box was made from.  Figured out what city they were from. Then hired investigators to find the plant.   They had etched down the chips on a board to make their own masks.  Except they did not understand that each board had a unique macaddr burnt in…

    We (Chrysler) only had about 10 of them (of course for manager’s PCs). 
    But I heard that GM had done a big buy from a supplier…