So, *@discuss.systems ; still trying to wrap me head around this IPv6 thing, couldn't sleep last night thinking about it; even though in the past I have successfully setup an IPv6 network via Hurricane Electric Tunnel and receiving a badge at the time for having set it up to the point I could have my #OpenWrt router pinged on the other end of the tunnel.

Had no actual #IPv6 connection at that point, but now I believe I do.

Now I have muddled through a few tutorials on the subject and I am confused as ever.

I have at my disposal, the tools subnetcalc and the ipaddr library of python which is capable of calculating address ranges based on CIDR notation and for telling you if an address is a network address ranges, from what part of the world, or if an unicast single host address.

Half way through watching a video that recommends first watching another video with a painfully German guy who seems to really know his stuff and looks like my old coworker Brewbaker were he a bit taller, they must be relatives.

Allowing the Delegation of Global Address prefix seems to allow for sub-sub netting amongst the original address space, and if you want to prevent this it you disallow it like a land lord disallowing subletting in the lease agreement.

Also, my Xfinity connection seems to indicate that this prefix will change weekly. And if I want any of my servers to keep their static address they seem as though they will need to be readdressed manually every week, with a Global static address since the downstream prefix of their subnet would change with the weekly prefix change. And then I would have to change the firewall rules too!!!

Also it seems that somehow #arp has been replaced by #ICMPv6 and some totally confusing process called Neighbor Detection #ND in which routers and hosts advertise and solicitate.

Also, Site-Local addressing with a FEC0 range appears to have replaced the 172.0.0.0, 10.0.0.0 and 192.168.0.0 ranges but these have also been deprecated so they shouldn't be used.

And the I didn't-get-an-address, address, 169.0.0.0 has been replaced by FE80 addresses but they can oddly still be communicated with.

Seems like a mess to me, but learning something new tends to be like that.

Any tips for the blind group of men trying to describe the elephant to each other you can provide me would be appreciated.

#IPv6

What year is today?

"Can I configure reverse DNS for #IPv6 PublicIpAddress resources?

No. #Azure DNS does not currently support reverse DNS (PTR records) for Azure-owned public IPv6 addresses."

https://learn.microsoft.com/en-us/azure/dns/dns-reverse-dns-for-azure-services#can-i-configure-reverse-dns-for-ipv6-publicipaddress-resources

The interfaces of a Linux host have only IPv6 link-local addresses assigned. The Linux kernel has learned a on-link prefix (without M flag, no prefixes with A flag) and a default IPv6 route.

Q: What happens when trying to send IPv6 packets to an global-unicast addresses from this host?

A: Packets are send from the link-local address to global-unicast addresses 😳 🤯

IP6 fe80::8c52:5aff:fe15:3720 > 2620:0:871:9000::77: ICMP6, echo request, id 17175, seq 7, length 64

#linuxnetworking #ipv6