Page 1 of 1

pool6 refused acquire: bad preferred prefix! (6)

Posted: Sun Feb 05, 2017 1:44 pm
by crodler
Hello,
Routeros 6.38.1 PPPOE Server with DHCPv6 PD enabled.
IPv6 pool: Prefix xxxx:yyyy::/52 Prefix length: 64
Client: Ubnt Airos6: DHCPv6 client on pppoe, Prefix Delegation with statefull DHCPv6 Server, IPv6 Prefix Length: 64 on lan.
Everything works correctly with IPv6, but on PPPOE Server i get the above error: pool6 refused acquire: bad preferred prefix! (6)

What's wrong?

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Fri Feb 17, 2017 2:31 pm
by oscarc
I've got similar error:
pool6 refused acquire: pool not found:


And I have the pool defined in both, server and client?

Any idea?

Thanks in advance

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Mon Feb 27, 2017 11:03 am
by SDFadfasdfadsf
same issue, DHCPv6 server is broken

I have a /56 from DHCPv6 client. Trying to hand out this /56 with DHCPv6 server, keeps getting this error in log

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Thu Aug 10, 2017 6:03 pm
by locodog
Problem is not in Mikrotik dhcpv6 server, when you set prefix length in ubnt lan interface to /64 it requests from Mikrotik /64 and that is != /60 configured in Pool, that's why error happens.
If you configure ubnt lan to request /60 and set stateless dhcp, there is no error in log, prefix is accepted and /64 is assigned to lan interface of ubnt.

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Thu Aug 10, 2017 6:43 pm
by ZeroByte
OP specified that the prefix-length in the pool is /64, not /60, so that may not be the problem for him.

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Sat Aug 12, 2017 12:55 pm
by locodog
I reject your reality and substitute my own!

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Thu Oct 18, 2018 11:33 am
by crodler
After update to 6.43.4 the ubiquiti client doesn't get prefix anymore and router throws above error continuously.

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Tue Oct 23, 2018 7:51 pm
by simeitg
Same problema here with CPE Intelbrás WOM 5000 MIMO. CPE is set to AUTO but get /64 instead of /56.

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Tue Oct 23, 2018 8:02 pm
by simeitg
Image
Image

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Tue Nov 06, 2018 7:45 pm
by simeitg
After update to 6.43.4 the ubiquiti client doesn't get prefix anymore and router throws above error continuously.
same here

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Mon Nov 19, 2018 5:32 am
by bearmeister
Found this post after searching for same symptoms - Did anyone find a resolution?
Thank you

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Mon Nov 26, 2018 10:31 pm
by simeitg
Found this post after searching for same symptoms - Did anyone find a resolution?
Thank you
Nothing yet!

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Fri Nov 30, 2018 9:29 am
by GZ15
For anyone wondering, we tried to downgrade the RouterOS on hEX Lite with this problem (we were running 6.43.4). The router itself didn't downgrade (consumed the ROS package - ?) but the DHCPv6 client started working. So it might be worth a shot for you till this is fixed.

Re: pool6 refused acquire: bad preferred prefix! (6)

Posted: Mon Jun 17, 2019 11:23 am
by frogale
Any news on that?