Version:
```
vyos@dhcp-server:~$ show ver
Version: VyOS 1.4.4
Release train: sagitta
Release flavor: kvm
Built by: autobuild@vyos.net
Built on: Thu 18 Dec 2025 16:20 UTC
Build UUID: a19109d0-ec1c-48ec-b239-14cd7a27926e
Build commit ID: f2bd2fba602ba5
Architecture: x86_64
Boot via: installed image
System type: KVM guest
Hardware vendor: QEMU
Hardware model: Standard PC (i440FX + PIIX, 1996)
Hardware S/N:
Hardware UUID: e4c9e12b-dbc5-4f1c-94e0-79f7021893fe
Copyright: VyOS maintainers and contributors
vyos@dhcp-server:~$
```
VyOS config:
```
set interfaces ethernet eth0 description 'WAN'
set interfaces ethernet eth0 dhcpv6-options duid '00:04:c0:00:00:ac:1d'
set interfaces ethernet eth0 dhcpv6-options pd 1 interface eth1 address '1'
set interfaces ethernet eth0 ipv6 address autoconf
set interfaces ethernet eth1 address '10.97.221.1/24'
set interfaces ethernet eth1 description 'LAN'
```
Assigned address/prefix on eth1:
```
$ show interfaces ethernet eth1
eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 52:18:01:3b:9a:d5 brd ff:ff:ff:ff:ff:ff
altname enp6s19
inet 10.97.221.1/24 brd 10.97.221.255 scope global eth1
valid_lft forever preferred_lft forever
inet6 2a05:bcc1:3:ff::1/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::5018:1ff:fe3b:9ad5/64 scope link
valid_lft forever preferred_lft forever
Description: LAN
```
interface where the DHCPc listens:
$
```
show interfaces ethernet eth0
eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 1e:d7:e3:44:40:ef brd ff:ff:ff:ff:ff:ff
altname enp6s18
inet6 2a05:bcc0:0:3:1cd7:e3ff:fe44:40ef/64 scope global dynamic mngtmpaddr proto kernel_ra
valid_lft 2591829sec preferred_lft 14229sec
inet6 fe80::1cd7:e3ff:fe44:40ef/64 scope link
valid_lft forever preferred_lft forever
```
VyOS SERVER:
```
set service dhcpv6-server shared-network-name XantionWAN3 subnet 2a05:bcc0:0:3::/64 prefix-delegation start 2a05:bcc1:3:: prefix-length '64'
set service dhcpv6-server shared-network-name XantionWAN3 subnet 2a05:bcc0:0:3::/64 prefix-delegation start 2a05:bcc1:3:: stop '2a05:bcc1:3:ff::'
$ show dhcpv6 server leases
IPv6 address State Last communication Lease expiration Remaining Type Pool DUID
------------------- ------- -------------------- ------------------ ----------- ----------------- ----------- -----------------------------------------------------
2a05:bcc1:3:ff::/64 active 2026/01/09 14:20:35 - - prefix delegation XantionWAN3 00:04:c0:00:00:ac:1d
```
$
```
show ipv6 route
Codes: K - kernel route, C - connected, S - static, R - RIPng,
O - OSPFv3, I - IS-IS, B - BGP, N - NHRP, T - Table,
v - VNC, V - VNC-Direct, A - Babel, F - PBR,
f - OpenFabric, t - Table-Direct,
> - selected route, * - FIB route, q - queued, r - rejected, b - backup
t - trapped, o - offload failure
...
C>* 2a05:bcc0:0:1::/64 is directly connected, bond0.61, 1d17h26m
C>* 2a05:bcc0:0:2::/64 is directly connected, bond0.62, 1d17h26m
C>* 2a05:bcc0:0:3::/64 is directly connected, bond0.63, 1d17h26m
C>* 2a05:bcc0:0:4::/64 is directly connected, bond0.64, 1d17h26m
C>* 2a05:bcc0:0:5::/64 is directly connected, bond0.65, 1d17h26m
S>* fc00::/7 [1/0] unreachable (blackhole), weight 1, 1d17h26m
C * fe80::/64 is directly connected, bond0.64, 1d17h26m
C * fe80::/64 is directly connected, bond0.63, 1d17h26m
C * fe80::/64 is directly connected, bond0.65, 1d17h26m
C * fe80::/64 is directly connected, bond0.61, 1d17h26m
C * fe80::/64 is directly connected, bond0, 1d17h26m
C * fe80::/64 is directly connected, bond0.62, 1d17h26m
C * fe80::/64 is directly connected, eth0, 1d17h26m
C>* fe80::/64 is directly connected, lo, 1d17h26m
```
No route to 2a05:bcc1:3:ff::1/64.
Reproduced in stream 2025.11