asus rt-ax88u ipv6 through wireguard client dhcp problem

[woji]

hello,
my ISP provides ONLY ipv4 but I need ipv6 for work and home IOT.

So I:
- bought RPI5 housing with public ipv4/32 and ipv6/64
- setup wireguard on RPI5
- updated my rt-ax88u to merlin (3004.388.8)
- setup WG client on merlin
- resolved router restart wireguard conn persistence (nightmare)

and I despite my router is behind double ipv4 nat, it has public IPV6 address and I can connect it from internet and reach ipv6 world from router and it works all ok.


now second stage is LAN DHCPv6 which seems to be the harder part.

my ipv6 settings in router www admin interface is set to passthrough.
router is now somehow in SLAAC and reports local ipv6 on all interfaces

I've created /jffs/configs/dnsmasq.conf.add with this content
```
# 2025-01-31, xxx, add support for DHCPv6

interface=wgc5
no-dhcpv4-interface=wgc5

# Enable router advertisements on wgc5
enable-ra
#ra-param=wgc5,high,1,0

# no tag = apply to all clients except tagged ??
dhcp-range=wgc5,xxxx:xxxx:xx:xxxx:8100::1000,xxxx:xxxx:xx:xxxx:8100::2000,72,864s
```

then I run
```
dnsmasq --test
ok
service restart_dnsmasq
ok
```

I tried to release dhcp on my macbook but I got no ipv6 from routers DHCPv6
I tried to reboot macbook but still no ipv6 address from router's DHCPv6.

so I
```
mv dnsmasq.conf.add dnsmasq.conf.off
service restart_dnsmasq
ok
dnsmasq --test
ok
```

all ok back on ipv4

dnsmasq documentation won't offer much about my required config. It looks quite unusual to tunnel ipv6 home over wg and make it ipv6 inet interface.

1. how can I get some debug messages from dnsmasq on merlin ?
I tried to add 2 lines to dnsmasq.conf.add
log-queries
log-dhcp

none in log

2.how can I setup dhcpv6 on merlin, to keep server dhcpv4 to all LAN clients and add dhcpv6 to most except some 3 clients (apple TV) where WG ipv6 tunnel might slowdown connectivity.
??

with kind regards

Adam

 

[ZebMcKayhan]

hello,
my ISP provides ONLY ipv4 but I need ipv6 for work and home IOT.

So I:
- bought RPI5 housing with public ipv4/32 and ipv6/64
- setup wireguard on RPI5
- updated my rt-ax88u to merlin (3004.388.8)
- setup WG client on merlin
- resolved router restart wireguard conn persistence (nightmare)

and I despite my router is behind double ipv4 nat, it has public IPV6 address and I can connect it from internet and reach ipv6 world from router and it works all ok.


now second stage is LAN DHCPv6 which seems to be the harder part.

my ipv6 settings in router www admin interface is set to passthrough.
router is now somehow in SLAAC and reports local ipv6 on all interfaces

I've created /jffs/configs/dnsmasq.conf.add with this content
```
# 2025-01-31, xxx, add support for DHCPv6

interface=wgc5
no-dhcpv4-interface=wgc5

# Enable router advertisements on wgc5
enable-ra
#ra-param=wgc5,high,1,0

# no tag = apply to all clients except tagged ??
dhcp-range=wgc5,xxxx:xxxx:xx:xxxx:8100::1000,xxxx:xxxx:xx:xxxx:8100::2000,72,864s
```

then I run
```
dnsmasq --test
ok
service restart_dnsmasq
ok
```

I tried to release dhcp on my macbook but I got no ipv6 from routers DHCPv6
I tried to reboot macbook but still no ipv6 address from router's DHCPv6.

so I
```
mv dnsmasq.conf.add dnsmasq.conf.off
service restart_dnsmasq
ok
dnsmasq --test
ok
```

all ok back on ipv4

dnsmasq documentation won't offer much about my required config. It looks quite unusual to tunnel ipv6 home over wg and make it ipv6 inet interface.

1. how can I get some debug messages from dnsmasq on merlin ?
I tried to add 2 lines to dnsmasq.conf.add
log-queries
log-dhcp

none in log

2.how can I setup dhcpv6 on merlin, to keep server dhcpv4 to all LAN clients and add dhcpv6 to most except some 3 clients (apple TV) where WG ipv6 tunnel might slowdown connectivity.
??

with kind regards

Adam

As your ipv6 prefix is static, why not just set it up in gui:
https://github.com/ZebMcKayhan/Wire...-ov-file#ipv6-over-wireguard-without-ipv6-wan

However, some tweaks are needed to get the rest of the way, it.e vpn-director ipv6 rule to send all ipv6 to wireguard - not possible in gui.