Router advertisements can announce a recursive DNS server (RDNSS) which local clients might like to use, eg:
https://github.com/radvd-project/radvd/blob/master/radvd.con...
Bad luck though if you are using, ahem, AIX or Windows Phone:
https://en.m.wikipedia.org/wiki/Comparison_of_IPv6_support_i...
there is RDNSS for router advertisments used with slaac. although it wasnt there initially and support for it might be lacking yet.
It's extra development and extra testing (in fact it's way more testing due to the combinatorial explosion of IPv4/IPv6 interface schemes).
That comes at a cost.
> ISPs and endpoint network devices are the only reason we don't have IPv6 more prevalent, combined with NAT, CGNAT etc. being good enough to keep the net hobbling along.
ISPs & endpoint devices are the majority of the Internet, as far as complexity is concerned. Upgrading the equipment for HW-acceleration of IPv6 (parity with IPv4) is very costly.
My router is an Edgerouter by the way.
I do recall seeing some of the configuration wizard stuff not having options for IPv6 in the past, but that's just for initial configuration anyway. Once you are done with that you do everything from the config tree anyway.
On the Unifi gear, the IPv6 UI that is there is marked "beta"
Just to be clear, one can configure the IPv6 firewall through the UI. One just has to use the config-tree rather than the easy firewall configuration.
Until Windows 10 this was correct, but now that Windows also supports RDNSS in Router Advertisements that is no longer the case.
My home network has been running SLAAC without DHCPv6 for years now.
DNS is critical. I'm not talking about registering an endpoint into a local DNS server (mydesktop.local), I'm talking about the endpoint knowing who to ask about google.com.
Switching back to my ISP's DNS meant getting a more suitable set of Akamai servers and reasonable download speeds again.
Such as Verizon who still doesn't support it on FIOS
That complexity is also part of why the Linux kernel's built-in support for IP autoconfig at boot time for network-based root filesystems (without using a userspace DHCP client) only supports IPv4.
The only thing I don't like about it, is how they created SLAAC (a way for a client to auto-configure its own IP address without DHCP) - but didn't enable routers to provide DNS information.
Therefore, in any useful deployment, you need to deal with SLAAC for IP allocation, and DHCPv6 for DNS information.
Outside of that, the spec is pretty decent.
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Also, damn every ISP and every router company that doesn't 100% support IPv6. Shockingly, this includes Ubiquiti, which is "supposed" to be medium-enterprise grade.
ISPs and endpoint network devices are the only reason we don't have IPv6 more prevalent, combined with NAT, CGNAT etc. being good enough to keep the net hobbling along.