Oui, voici la conf et un bout de dump
root@3615nexuscore:~# cat /etc/dhcpcd.conf
noipv4
noipv6rs
allowinterfaces ppp-milkywan
interface ppp-milkywan
ipv6rs
noipv4
ia_na 0
ia_pd 1 enp1s0np0.40/0 enp1s0np0.50/1 enp1s0np0.60/2 enp1s0np0.70/3 enp1s0np0.80/4 enp1s0np0.90/5
root@3615nexuscore:~# tcpdump -ni ppp-milkywan udp port 546 or port 547 -v -c 2
dropped privs to tcpdump
tcpdump: listening on ppp-milkywan, link-type LINUX_SLL (Linux cooked v1), snapshot length 262144 bytes
18:27:05.993200 IP6 (flowlabel 0x38946, hlim 1, next-header UDP (17), payload length 147) fe80::fad4:b5d6:d1c1:58d1.dhcpv6-client > ff02::1:2.dhcpv6-server: [udp sum ok] dhcp6 solicit (xid=926149 (client-ID hwaddr/time type 772 time 843123177 000000000000) (IA_NA IAID:0 T1:0 T2:0) (IA_PD IAID:1 T1:0 T2:0) (option-request opt_82 opt_83) (elapsed-time 5935) (vendor-class))
18:28:02.401084 IP6 (flowlabel 0x38946, hlim 1, next-header UDP (17), payload length 147) fe80::fad4:b5d6:d1c1:58d1.dhcpv6-client > ff02::1:2.dhcpv6-server: [udp sum ok] dhcp6 solicit (xid=926149 (client-ID hwaddr/time type 772 time 843123177 000000000000) (IA_NA IAID:0 T1:0 T2:0) (IA_PD IAID:1 T1:0 T2:0) (option-request opt_82 opt_83) (elapsed-time 11575) (vendor-class))
2 packets captured
2 packets received by filter
0 packets dropped by kernel
root@3615nexuscore:~#