On Thu, 29 Jun 2017, William Herrin wrote:
Heck, I’m gonna do whatever it takes to NOT subnet on bits with my v6
deployment. Hopefully with v6, gone are the days of binary subnetting math.
I hedged my bets when I laid out our v6 space at my previous $dayjob. We used /126s for point-to-point links, but carved out a /64 for each point-to-point link in our IPAM system. That way, if we ever encountered a device that wouldn't play nicely with a /126 on a point-to-point link, we could just change the mask to /64 (or something else, if the device requires a byte or nibble boundary) on the interface and any relevant ACLs and not have to re-provision addresses for the link. I seem to recall that our upstreams generally standardized on /126s for point-to-point interconnects to us. We had one interconnect that was a /64, but that also wasn't a point-to-point link. jms