Now that the great network migration phase two is pretty stable, where I have the new Eero providing the backbone and a pair of name servers providing DNS with a hand managed zone, it’s time for planning the next phase of the operation. That is to say, DHCP services.
For the most part, I stick to IPv6 addresses now with an IPv6 Unique-Local providing the internal definition of my home.arpa environment. Eero seems to let clients SLAAC away but at some point, I need to snoop closer on its IPv6 support to see if it is doing any kind of goodness like RDNSS/DNSS, but it mostly does DHCPv4.
So, I’m seeing two points of interest here for my DNS arrangements.
Option A.) Ignore the IPv4 world totally and setup DHCPv6 services for my dynamic updates needs. After all, I mostly want AAAA-records not A-records.
Option B.) Set Eero to the good ol’ you’re on your own pal mode and setup both DHCPv4 and DHCPv6 services.
Perhaps I will start with option A, since it is closer to DWIW and should get me what I want; which is IPv6 with dynamic updates to my local domain. But here’s a little thought for option B using Eeero’s default /22 network as a point of reference for the addressing scheme.
192.168.4.0/22 -> 192.168.4.1 - 192.168.7.254
192.168.4.1/22 -> gateway.home.arpa
192.168.7.255/22 -> broadcast
192.168.4.1-16 -> range for routing services; e.g. eero/ap.
192.168.4.17-254 -> deprecated, reserved for fallback to eero.
192.168.5.0-254 -> range for network services; e.g., dns, dhcp
192.168.6.0-255 -> DHCPv4 pool
192.168.7.0-254 -> | ~512 addresses, half the space.
This would effectively give a static space equal to the first /24 worth of the network that’s intended to be hands of for the oh-shit plan. While the DHCPv4 leasing is pretty aggressive on the Eero, I don’t think I’ve see any devices allocated higher than the first octet. The idea being nothing that’s not a router, an access point, or something getting a lease from switching from my server back to the Eero’s DHCP server should land in this portion of the network.
Following that would be a static space equal to the second /24 worth of the network, intended to be allocated for services. Either by static allocation or just making a static reservation. Let’s just say, as much as I like technology, I’ve managed long enough with a lone /24 for my entire household that I’m sure I’m not going to pull 254 static IPv4 addresses out of my ass anytime soon.
Meanwhile the portion of the network roughly equal to the last /23 of the network, effectively the back half of the network and least likely to be interfered with if the Eero ever happens to ‘forget’ its in static mode, would be client addresses. Which are very much intended to be “Don’t give a fuck about” addresses in the sense that the only IPv4 addresses I use are cases like using dig to poke one of my name servers and not wanting to type its IPv6.
One of the food for thought items on my plate is whether or not I want to ‘unretire’ my old file server, Cream, and turn it into a replacement for ns2. Right now, ns2 is running off a Raspberry Pi Zero W that was originally intended to be a RaSCSI drive for my PowerBook.
Ahh, well, I’ve got other things to do for the moment.