[ipv6-wg] Looking for a secon opinion on using ULA along with GUA for residential access

Hello,

During the evaluation of a new model of CPE for our residential access
we found one of the suppliers providing an option to announce a ULA
prefix in addition to the GUA prefix obtained from DHCP-PD. I would like
some second opinions regarding auch a practice.

>From my point of view, if ULA is enabled:
 - it allows the client's LAN to stay IPv6-enabled even when the
 internet connection is down. It is a simpler version compared to the
 use of link-locals.
 - if the "auto" version of the setting is used, the ULA prefix will
 risk changing when changing the CPE, which is less than optimal.

If ULA is disabled:
 - business as usual; when internet is down the client will only have
 RFC1918 (v4) + link-local (v6)

So, is it worth enabling an additional ULA on the LAN ?

-- 
Radu-Adrian FEURDEAN