Community discussions

 
User avatar
floeff
newbie
Topic Author
Posts: 30
Joined: Sat Jan 28, 2017 6:39 pm
Location: Germany
Contact:

DHCPv6 DUID change - bug?

Sun Apr 16, 2017 7:40 pm

I've changed my MAC address via
/interface ethernet set ether1 mac-address=
This new MAC seems to be used for the DHCPv4 client. However, for creating the DUID for DHCPv6, still the original MAC address is used.
Is there any way to work around that? I need to change the DUID in order to get a new/larger v6 subnet via PD
 
flazzarini
just joined
Posts: 19
Joined: Thu Jun 13, 2013 11:05 am

Re: DHCPv6 DUID change - bug?

Thu Jul 13, 2017 10:02 am

I've had exactly the same issue. The DUID generated by ROS was done using another interface's mac address as the one I used to created my PPPOE session to my ISP. I've had to change mac addresses on the interfaces to make the DHCPv6 Request work.

It would be really nice if one could force reset the DUID value in ROS.
 
User avatar
floeff
newbie
Topic Author
Posts: 30
Joined: Sat Jan 28, 2017 6:39 pm
Location: Germany
Contact:

Re: DHCPv6 DUID change - bug?

Thu Jul 13, 2017 3:41 pm

What should work (learned from MikroTik support) is to factory reset the device. If you restore the text backup (RSC file), the DUID is regenerated first time you use DHCPv6. Not sure what happens with a binary backup though.
 
tibobo
newbie
Posts: 39
Joined: Tue Sep 27, 2016 8:54 am

Re: DHCPv6 DUID change - bug?

Wed Sep 27, 2017 1:46 am

What should work (learned from MikroTik support) is to factory reset the device. If you restore the text backup (RSC file), the DUID is regenerated first time you use DHCPv6. Not sure what happens with a binary backup though.
This works but still doesn't address the case where you have to set up an arbitrary DUID like when you're hosted at Online.net as described here : viewtopic.php?f=2&t=114389&p=620446#p620446
Which is also my problem…

It seems that RFC 3315 says you should not change the DUID (viewtopic.php?f=2&t=57582&p=509167&hilit=duid#p294781), but what harm would it actually cause to let us change that setting ?

Arnaud
 
User avatar
ZeroByte
Forum Guru
Forum Guru
Posts: 4048
Joined: Wed May 11, 2011 6:08 pm

Re: DHCPv6 DUID change - bug?

Wed Sep 27, 2017 7:22 am

Are you using Comcast? When you first set a prefix-hint on their service, a strange thing happens. Packet captures show that the primary server gives you the same /64 you already had, and the backup server gives a /60, but since it replies later than the primary, the Mikrotik router will have already bound the /64 offered by the primary. The only fix I've seen with them is to just disable DHCPv6 for a couple of days while your lease expires. After that, the primary server will honor the /60 in prefix-hint when you re-activate the dhcpv6 client.

(They may have fixed this by now but I haven't tried messing around to see whether this is the case or not)

As stated in the thread, the DUID is intended to be a unique identifier for your device and shouldn't be changed. Honestly, I think people should complain to Comcast but doubt that's going to budge them any - most tech support people I've talked to don't even know about IPv6 at all.
When given a spoon,
you should not cling to your fork.
The soup will get cold.
 
tibobo
newbie
Posts: 39
Joined: Tue Sep 27, 2016 8:54 am

Re: DHCPv6 DUID change - bug?

Wed Sep 27, 2017 9:09 am

No, I'm not using Comcast, I'm using Online.net, a french hosting company : https://www.online.net/en
They chose to implement IPv6 PD the following way : https://documentation.online.net/en/ded ... pv6/prefix
Unfortunately, I cannot change the DUID in RouterOS, so I had to change the interface mac address in vmware.
But even then, with the proper DUID, I can't find the correct settings and never get an address !
 
Florian
Frequent Visitor
Frequent Visitor
Posts: 50
Joined: Sun Mar 13, 2016 9:45 am
Location: France

Re: DHCPv6 DUID change - bug?

Wed Oct 31, 2018 6:38 pm

Any news on this ? SFR, a french ISP, need a specific DUID. I don't want to factory reset my router, then change the mac adress (of eth1 since RoS seems to use this one event if it's not connected...), and then enable ipv6, only for that... A simple duid variable in the dhcpv6 client would do the trick. Ubuiquiti ERL's are allowing that... Come on Mikrotik...
- Sorry for my english -
 
Florian
Frequent Visitor
Frequent Visitor
Posts: 50
Joined: Sun Mar 13, 2016 9:45 am
Location: France

Re: DHCPv6 DUID change - bug?

Sat Nov 03, 2018 11:25 am

Can we at least have the option to reset the duid, from a chosen eth interface, without having to factory reset the whole thing, please ?
- Sorry for my english -
 
Florian
Frequent Visitor
Frequent Visitor
Posts: 50
Joined: Sun Mar 13, 2016 9:45 am
Location: France

Re: DHCPv6 DUID change - bug?

Fri Nov 09, 2018 10:45 pm

Alright, so I did a reset configuration, then change the ether1 mac address, the create a dhcp6 client, and still, it's the original mac from ether1 who is used for the duid.

The factory reset isn't working anymore ?

Thx in advance.

Edit : ok, I had to disable dhcp and IPv6 package, reboot, reset conf, reboot, change the mac, reboot, activate package, reboot, and then the new duid for ipv6 was generated based on eth1.
- Sorry for my english -

Who is online

Users browsing this forum: Frostbyte, Kindis, petrz, TurboCow and 35 guests