Hi,

I got this mac for most of my interfaces, is this a bug?
Can someone shed some light on this issue?

Won't it cause problems when multiple network interfaces
have the same mac?

exellent question - now we only need to guess other details

I got it too, svn trunk, ZyXEL NBG-419N, newly supported since a few months by openwrt. What additional info is needed?

Multiple network with the same MAC is no problem. Same MAC in the same network is a problem. Multiple brands of professional network equipment make use of this, because registring the vendor part of the MAC address cost money (although not all vendors register their MACs).

You'll find that most of the time, when you configure a trunk, you'll see the same MAC address configured on all layer3 interfaces.

Although its interesting to know where this MAC comes from, it should not give a problem. Unless of course you connect two of those routers.

(Last edited by Adze on 24 Nov 2011, 19:16)

In ZyXEL NBG-419N case wifi MAC is correct, corresponds to one of the MACs written on the box, but all other MAC addresses (br-lan, eth0, eth0.1, eth0.2) are 00:11:22:33:44:55.

Same on a DIR-600 B1 (trunk r28963). wifi is OK, but all other MAC adresses are 00:11:22:33:44:55.

Should be the MAC listed on the device. Strange, isn't it.

Update: Mmhh 00:11:22:33:44:55 show up in the Luci. Can't reboot, check later and update results.
So we might know where this is comming from ;->

This is realy strange, I added manually the correct MAC and it seems too work.

I also have the WAN MAC faked for my cable provider.

tom

(Last edited by f41SIXXS on 3 Dec 2011, 10:28)

Just FYI - support for getting MAC addresses from ZyXEL NBG-419N factory partition was added a few hours ago to svn.

Thanks for all the help!

So it's a dummy mac and it is set when when the "real" mac cannot be retrieved because of shortcomings of the driver.
I have two dir-600 in a network. That sounds like asking for trouble.

You can try to do what I did. # cat /proc/mtd
dev:    size   erasesize  name
mtd0: 00030000 00010000 "u-boot"
mtd1: 00010000 00010000 "u-boot-env"
mtd2: 00010000 00010000 "factory"
mtd3: 000d0000 00010000 "kernel"
mtd4: 002e0000 00010000 "rootfs"
mtd5: 00110000 00010000 "rootfs_data"
mtd6: 003b0000 00010000 "firmware"

# dd bs=65536 if=/dev/mtdblockX of=/tmp/mtdX.bin where X is 0, 1, 2. Copied 3 files to my PC by scp.
Examined (with wxHexEditor) mtdX.bin and found that MAC addresses (which are written on the router) are in mtd2.bin and start at offsets 4 and 40: CC 5D 4E...
If you find where they are, post here, and I will tell you what to do next.

Thanks; but what I do atm. is to change the mac at startup. I can get the mac from the wifi device and change it a bit. It does the job.

Yes, that's a workaround. But if you did what I asked, it could help others in the future, i.e. openwrt could use correct MACs from the start.

Should be fixed in svn - https://dev.openwrt.org/changeset/29471

Oh, ok! I thought you wanted me to change the mac in the binary which seemed a bit too laborious.

Thanks for the fix!

(Last edited by mwarning on 8 Dec 2011, 08:43)