vyos@R1:~$ show dhcpv6 server leases 
IPv6 address        State    Last communication    Lease expiration     Remaining    Type               Pool         IAID_DUID
------------------  -------  --------------------  -------------------  -----------  -----------------  -----------  -----------------------------------------------------
2001:db8:290::/64   active   2021/04/23 14:52:48                                     prefix delegation  VyOS-DHCPv6  00:00:00:00:00:01:00:01:28:15:9b:bd:50:00:00:06:00:00
2001:db8:3456::15b  active   2021/04/27 05:07:51   2021/04/27 17:07:51  10:28:27     non-temporary      VyOS-DHCPv6  00:00:00:00:00:01:00:01:28:15:9b:bd:50:00:00:06:00:00

>>> from vyos.config import Config
>>> import pprint
>>> conf = Config()
>>> # no mangling
... tmp = conf.get_config_dict(['simple'], get_first_key=True)
>>> pprint.pprint(tmp)
{'some-tag-node': {'some-foo': {'just-a-node': {'single-value': 'bar'}},
                   'some-other-foo': {'just-a-node': {'multiple-value': ['first',
                                                                         'second']}}}}
>>> # standard mangling
... tmp = conf.get_config_dict(['simple'], get_first_key=True, key_mangling=('-', '_'))
>>> pprint.pprint(tmp)
{'some_tag_node': {'some_foo': {'just_a_node': {'single_value': 'bar'}},
                   'some_other_foo': {'just_a_node': {'multiple_value': ['first',
                                                                         'second']}}}}
>>> # mangling with no_tag_node_value_mangle=True
... tmp = conf.get_config_dict(['simple'], get_first_key=True, key_mangling=('-', '_'), no_tag_node_value_mangle=True)
>>> pprint.pprint(tmp)
{'some_tag_node': {'some-foo': {'just_a_node': {'single_value': 'bar'}},
                   'some-other-foo': {'just_a_node': {'multiple_value': ['first',
                                                                         'second']}}}}
>>>

set container name alp02 image 'alpine'
set container name alp02 network NET01 address '192.0.2.1'
set container network NET01 ipv4-prefix '10.0.0.0/24

time="2021-04-14T00:52:03+03:00" level=error msg="Error adding network: failed to allocate all requested IPs: 192.0.2.1"
time="2021-04-14T00:52:03+03:00" level=error msg="Error while adding pod to CNI network \"NET01\": failed to allocate all requested IPs: 192.0.2.1"
Error: unable to start container "60f20a2b517b4f828bef5683cd8a20504aa984648a0911f7f8df5c1a064d2625": error configuring network namespace for container 60f20a2b517b4f828bef5683cd8a20504aa984648a0911f7f8df5c1a064d2625: failed to allocate all requested IPs: 192.0.2.1

 sudo cat /run/accel-pppd/pppoe.conf 
### generated by accel_pppoe.py ###
[modules]
log_syslog
pppoe
shaper
chap-secrets
ippool
auth_pap
auth_chap_md5
auth_mschap_v1
auth_mschap_v2

ipv6pool
ipv6_nd
ipv6_dhcp

set service pppoe-server ppp-options ipv6 allow

configure
set system sysctl custom net.ipv6.conf.default.addr_gen_mode value 0
commit