Starting with 1.3-rolling-202007251937 (it works in 1.3-rolling-202007251937), the list of prefix-delegated interfaces dhcpv6_pd_interfaces never makes it to the template in /usr/share/vyos/templates/dhcp-client/ipv6.tmpl.
I believe the change likely related to the get_config_dict() changes in T2653 that were merged on July 25.
To demonstrate, as far as I can tell, have any config with DHCPv6-PD, such as:
... interfaces { ethernet eth0 { address 1.2.3.4/29 address dhcpv6 dhcpv6-options { prefix-delegation { interface eth1 { address 1 sla-id 1 sla-len 4 } interface eth2 { address 1 sla-id 2 sla-len 4 } } ipv6 { address { autoconf } } } ethernet eth1 { address 192.168.1.1/24 } ethernet eth2 { address 192.168.10.1/24 } } ...
And then note the following contents of /run/dhcp6c/dhcp6c.eth0.conf:
# generated by dhcp.py # man https://www.unix.com/man-page/debian/5/dhcp6c.conf/ interface eth0 { request domain-name-servers; request domain-name; send ia-na 1; # non-temporary address }; id-assoc na 1 { # Identity association NA };
There's no send ia-pd 2; # prefix delegation or id-assoc pd 2 { section, so it seems like the new config code isn't propagating the dhcpv6_pd_interfaces value to the _DHCPv6 class in vyos/ifconfig/dhcp.py from vyos/ifconfig/interface.py.
I also tried setting int eth eth0 dhcpv6-options temporary just to see if that made it to the config file. It did not.