client.conf

$ cat /etc/systemd/system/netns.service

[Unit]
Description=Network Namespace Service

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/bin/ip netns add physical
ExecStart=/bin/ip link set enp3s0 down
ExecStart=/bin/ip link set wlp2s0b1 down
ExecStart=/bin/ip link set enp3s0 netns physical
ExecStart=/bin/iw phy phy0 set netns name physical
ExecStart=/bin/ip -n physical link add wg0 type wireguard
ExecStart=/bin/ip -n physical systemctl start systemd-networkd.service
ExecStart=/bin/wg setconf wg0 /etc/wireguard/client.conf
ExecStart=/bin/ip address add fc00:20/7 dev wg0
ExecStart=/bin/ip link set wg0 up
ExecStart=/bin/ip -6 route add default dev wg0
ExecStop=/bin/ip -n physical link set enp3s0 down
ExecStop=/bin/ip -n physical link set wlp2s0b1 down
ExecStop=/bin/ip -n physical link set enp3s0 netns 1
ExecStop=/bin/ip netns exec physical iw phy phy0 set netns 1
ExecStop=/bin/ip netns exec physical systemctl stop systemd-networkd.service
ExecStop=/bin/ip link del wg0
ExecStop=/bin/ip netns del physical

[Install]
WantedBy=multi-user.target



$ cat /etc/systemd/network/ethernet-dhcp.network

[Match]
Name=enp3s0

[Network]
DHCP=ipv6



$ cat /etc/wireguard/client.conf

[Interface]
PrivateKey = OAT5r6E1hid***iVBnY=
ListenPort = 52345

[Peer]
PublicKey = aMC3f6kw***UDQVwo=
EndPoint = [2a01:4f8:***:***::5]:40111
AllowedIPs = fc00::10/7



$ wg

interface: wg0
  public key: vWjIpwbIZD***4gR2zQE=
  private key: (hidden)
  listening port: 52345

peer: aMC3f6kw***UDQVwo=
  endpoint: [2a01:4f8:***:***::5]:40111
  allowed ips: fc00::10/7
  latest handshake: 14 seconds ago
  bandwidth: 42.15 KiB received, 51.31 KiB sent



$ ip a

1: lo: <LOOPBACK> mtu 65536 qdisc noqueue state DOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
4: wg0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1423 qdisc noqueue state UNKNOWN group default qlen 1
    link/none
    inet6 fc00::20/7 scope global
       valid_lft forever preferred_lft forever
    inet6 fe80::52**:****:**5a:c6bd/64 scope link flags 800
       valid_lft forever preferred_lft forever



$ ip -6 route

fc00::/7 dev wg0  proto kernel  metric 256  pref medium
fe80::/64 dev wg0  proto kernel  metric 256  pref medium
default dev wg0  metric 1024  pref medium



$ ip netns exec physical ip a

1: lo: <LOOPBACK> mtu 65536 qdisc noqueue state DOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc state UP group default qlen 1000
    link/ether f0:de:f1:b1:54:58 brd ff:ff:ff:ff:ff:ff
    inet6 2a02:2698:****:***:****:****:feb1:5458/64 scope global mngtmpaddr dynamic
       valid_lft 595sec preferred_lft 595sec
    inet6 fe80::f2**:****:**b1:5458/64 scope link
       valid_lft forever preferred_lft forever
3: wlp2s0b1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether 64:27:37:01:4d:10 brd ff:ff:ff:ff:ff:ff