El 11/10/21 a las 11:55, Tom Yates escribió: > i need a way to stop anything from changing my external MAC address, > as my ISP is extremely sensitive to additional MAC addresses appearing > on my external NIC. > > i have done > > sudo nmcli conn mod eno1 802-3-ethernet.cloned-mac-address permanent > > and it's improved matters, but here's an example of it going wrong > even so, from "tcpdump -n -n -e -i eno1 src 185.219.108.121" (which is > my ipv4): > > 10:23:58.210653 ac:1f:6b:6c:5a:6e > bc:30:5b:f7:3e:c8, ethertype IPv4 > (0x0800), length 114: 185.219.108.121.53002 > 198.252.206.25.443: > Flags [P.], seq 2018:2066, ack 5333, win 501, options [nop,nop,TS val > 4035938817 ecr 1709670339], length 48 > 10:23:58.405154 ac:1f:6b:6c:5a:6e > bc:30:5b:f7:3e:c8, ethertype IPv4 > (0x0800), length 66: 185.219.108.121.44534 > 216.58.212.234.443: Flags > [.], ack 21641, win 501, options [nop,nop,TS val 805137946 ecr > 1062125308], length 0 > 10:23:58.447030 ac:1f:6b:6c:58:2d > ff:ff:ff:ff:ff:ff, ethertype ARP > (0x0806), length 60: Request who-has 185.219.108.1 tell > 185.219.108.121, length 46 > 10:23:58.447466 ac:1f:6b:6c:58:2d > bc:30:5b:f7:3e:c8, ethertype IPv4 > (0x0800), length 342: 185.219.108.121.68 > 185.219.108.1.67: > BOOTP/DHCP, Request from ac:1f:6b:6c:58:2d, length 300 > 10:23:58.629131 ac:1f:6b:6c:5a:6e > bc:30:5b:f7:3e:c8, ethertype IPv4 > (0x0800), length 98: 185.219.108.121 > 8.8.8.8: ICMP echo request, id > 105, seq 67, length 64 > > note the first two frames coming from ac:1f:6b:6c:5a:6e, the real MAC > address, which has been happily all over the headers of the previous > several thousand frames, but then two frames from ac:1f:6b:6c:58:2d, > which *utterly* screw up my connection to my ISP. the old MAC address > continues to be on some of the outgoing traffic. > > i have some grounds for thinking that the first or second frame with > the "bad" mac address is always a BOOTP/DHCP frame, so i'm open to the > idea that this is dhclient being "helpful", rather than NM. > > does anyone have any idea which daemon or service is responsible for > this MAC-rebadging, and/or how i might stop it? > > Hello Perhaps the solution is this: https://access.redhat.com/solutions/70215HWADDR= Never see in CentOS but yes in Proxmox (bridge). Adding HWADDR= was a solution for me. But note this article asks you to change HWADDR= to MACADDR= Hope helps