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by citrin_ru 1788 days ago
You still need DHCP for more than one reason: 1. Prefix delegation 2. DDNS (DHCP server can register a client IP in DNS)

I've used SLAAC in my home LAN when used IPv6 ISP. Now I use IPv4-only ISP (in my area no ISP supports IPv6) and don't miss SLAAC at all.

Over the years I've used DHCP in many smallish LANs (<=100 hosts) and never had any problems with it.
1 comments
adev_ 1788 days ago
> You still need DHCP for more than one reason:

1) You generally do not need prefix delegation in v6: you use IPv6 like it has been designed too: routable address everywhere, /64 per default and prefix over it.

2) SLAAC is stateless and deterministic: One MAC address will always gives you the same IP. That makes DDNS mostly useless.

But even if you really want to do it, it is also possible with SLAAC.

link
citrin_ru 1788 days ago
1) Precisely because you are not supposed to use NAT with IPv6 you need prefix delegation: CPE (home router) in addition to an external address (can be obtained via SLAAC) needs a network prefix (/64 or more) which it can use for LAN segment(s). DHCPv6 PD is also used in 464XLAT.

2) Address with SLAAC is deterministic but you need to know MAC address for each device to generate DNS zone. In home LAN I don't want to maintain a database of MAC address for all devices (with internet connected everything there are quite a few of them) and also at home I trust my devices not to spoof hostname in DHCP request so DHCP based DDNS works fine for me.

link