FYI ----- Forwarded message from Michael Richardson <mcr@sandelman.ca> ----- From: Michael Richardson <mcr@sandelman.ca> Date: Tue, 17 May 2011 13:10:40 -0400 To: Eugen Leitl <eugen@leitl.org> cc: debian-ipv6@lists.debian.org Subject: Re: [vserver] assigning less than /64 to individual guests X-Mailer: MH-E 8.1; nmh 1.1; XEmacs 21.4 (patch 22) >>>>> "Eugen" == Eugen Leitl <eugen@leitl.org> writes: Eugen> Just sent that to the vserver list, but figured this is at Eugen> least as relevant. Eugen> So am I in the clear to parcel out a /64 in /80s, as long as Eugen> all the /80 are all on the same LAN or VLAN? No autoconfig Eugen> breakage ensues? Is 48 bits really enough for anybody? If you are saying that you will allocate /80s to each vserver, but actually they will not be layer-2 isolated from each other, this is just an administrative partition, then I think it's a good idea. You can't use autoconfig for the parts that are in the /80s. You can arrange for your /80s to never overlap the autoconfigured stuff. OUI-64s, when generated from OUI-48s (i.e. mac addresses) always have ff:fe as the middle 16 bits. In addition, bit 6 in the OUI-64 (which is bit 1 in little bit-endian, the bit after the "broadcast" bit) will be set if the OUI-64 is believed to be globally unique. Note that if you have IPv6 Privacy Extensions on, then autoconfig will not necessarily set bit 6. I would have to lookup to determine in fact privacy extensions will set the middle 16 bits in any predictable fashion. Permitting autoconfig to work seems like a nice thing to retain. -- ] He who is tired of Weird Al is tired of life! | firewalls [ ] Michael Richardson, Sandelman Software Works, Ottawa, ON |net architect[ ] mcr@sandelman.ottawa.on.ca http://www.sandelman.ottawa.on.ca/ |device driver[ Kyoto Plus: watch the video <http://www.youtube.com/watch?v=kzx1ycLXQSE> then sign the petition. -- To UNSUBSCRIBE, email to debian-ipv6-REQUEST@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org Archive: http://lists.debian.org/27236.1305652240@marajade.sandelman.ca ----- End forwarded message ----- -- Eugen* Leitl <a href="leitlhttp://leitl.org">leitl</a> http://leitl.org ______________________________________________________________ ICBM: 48.07100, 11.36820 http://www.ativel.com http://postbiota.org 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE