Point to point addressing in the WAN can be /64 or /127. There has been a lot of debate on which is better. For reducing operational complexity, /64 is a good choice for point to pint links, despite the waste.
The IPv6 address plan considerations section is quite good. It cites the now-historical RFC3627 which encouraged /64 use, but RFC6164 (http://tools.ietf.org/html/rfc6164) is the "pro" argument for /127 links.
https://supportforums.cisco.com/thread/2174969 is a good discussion of options to address point to point links and some of the pros and cons of each. Beware the risks of building discontiguous subnets and attendant summarization issues.
IPv6 ULA addresses are the equivalent of private IPv4 ranges. You can also use link local, with the risk that diagnostic tools like tracroute may not work as expected.
For the GRE case, just pick a subnet range from one side.
This document gives several answers on frequently asked questions for PFRv3 channel state behavior.
Q1: What are all the channel operational states from a BR (border role) perspective and what are the rules/conditions to be in each st...
The need was to reach an host inside a LAN through a VPN connection managed by the LAN gateway (Cisco 1921).
The LAN gateway performs NAT and there was a dedicate nat rule for the host i wanted to reach through VPN.
I couldn't connect to the hos...
We have 3 identical switches configured by someone else and would like to claim some of the Gigabit ports(G1/G2/G3/G4) for use on servers. When we try to change the wiring and configuration, we run in to connectivity issues. Attached is a des...