My team works with an allotment of IPv4 and IPv6 space, which is given to us from a larger organization in our company (we treat them like and ISP, where we request and are given IP space and allocate this across our buildings and sites as we deem appropriate), and have been given several /58's and /59's to make do with, which has been fine for years. Now we are looking at how to better allocate these resources, and I am curious if anyone has decided to carve up smaller than a /64?
My thoughts are, that while we currently use RA for IPv6 autodiscovery, and a /64 is the smallest network the RFC accounts for, I could chop a single /64 into several thousand /96's and uses these for PTP IPv6 routing only. This would save us a ton of IPv6 space, which as we deploy more and more Vlan interfaces and our network grows, I can see us running out of in the coming year(s), which would require asking for more IPv6 space, that we really don't need. Doing so would only be for PTP IPv6 routed links, and not use stateless autoconfig, and would allow us to re-IP current IPv6 PTP's using these /96 network and reclaim a large portion of our /64 space which was already deployed as PTP links.
We may still go this direction, however taking a /64 all the way down to a /126 would be quite a chore, so we may just go ahead and use this spec and reserve the entire /64 for PTP only, and just start from one end and track usage of the address space as we begin to parse it out for use.
** Edit - Correction, I assume you mean a /127 which is the equivalent of an IPv4 /30 network?
I had found some whitepapers and RFC on using /127's and how it was not recommended but with good understanding and proper use was acceptible, nothing I found on /126's.
I think I like Leo's solution the best, in order to prevent accidents and ease of administration. While I am not very concerned about running low on IPv6 space, we want to use it as best we can since we have to alter our BGP peering whenever we run out and are given more, and this solution would keep that churn lower.
This would be for PTP use only, we do use SLAAC for vlan interfaces currently, with the other-config-flag, to allow us to push IPv6 DNS pools to the clients as an interim step to going full v6 DHCP, so we will still use /64's here of course.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.