I have a couple of devices where the active MAC address changes (which breaks the hotspot bypass setup so I can't manage them!).
This is happening when the WLAN interface comes up because a client has connected - because the newly active WLAN has a lower MAC address than the current bridge MAC address the bridge adopts the MAC of the new WLAN interface.
How can I stop this? I notice that in winbox there is an 'admin mac address' option but I can't find it in the Docs - can I specify the MAC of a specific interface in there or do I need to assign a unique MAC to the Admin MAC.

I also noticed that there was a auto-mac=yes setting on the command line (Which also doesn't appear to be documented). Anyway I tried editing auto-mac=no & now have locked myself out of the unit... as it has disappeared from the IP network and also the neighbour table. The wireless link is still up but I can't mac telnet to the wireless link MAC address... Any suggestions how to get back in without taking my serial cable up the mast?

David

http://wiki.mikrotik.com/wiki/Manual:In ... face_Setup

admin-mac and auto-mac documentation.

For MAC telnet, try other MAC addresses on the device. Might be serial port time, though. Safe mode is good for these kind of changes.

Duh - how did I not see those (although the integrated help in winbox does go to the 'old' PDF manuals...)

Ok so admin-mac=0's and auto-mac=no so that's why it won't play!

David

Also, if you look up 'locally administered MAC address' you can find out how to construct administratively assigned MAC addresses that will never clash with any burnt in address of an interface. That's preferable to re-using an interface address, or making a universal MAC and risking a clash, unlikely as it may be.

That was my next question - do I use an interface MAC address or not. From similar usages on other kit it is usual that the interface HAS to be 'up' if you are re-using the MAC address so I assume it is the same on ROS.
IIRC the locally administered MAC address range has a bit set at the high order end (The MSB set is for multicast, the next one down is the locally administered flag.) So I can just have a policy of setting that one in a copy of (say) the ethernet interface MAC address....

David

Yup, that would work well.

I've been having the same problem but if I assign the ether1 mac address to the admin-mac address of the bridge I still lost connection because the wireless interface has a higher mac. So if I add the ether1 mac to the hotspot gateway ARP list and remove the bad host info for the hotspot host list it comes back with the rite mac and ip info.
I would like a better way of doing this.
Is there a list of usable local mac's?

Is it a bad idea to set the bridge and the wireless interface to the ether1 mac address?

Anyone? yes, no, maybe!