Fresh install dont get IPV6 internet

[PTwrt]

Architecture: MediaTek MT7621 ver:1 eco:3 | ramips/mt7621
OpenWrt 23.05.2

Hi, I installed openwrt and the clients dont have IPv6 internet but get a IPv6 address. Router have IPv6, is a fresh install without any modification in any config file.

Any guess? Is the /128 address?

Thanks for any help

[mk24]

Run ifstatus wan6. If you don't have a routable prefix you will need to use relay mode to put the lan devices in the same /64 GUA that you do have. This is common on LTE connections. What is the ISP technology (fiber, cable, etc)?

[PTwrt]

Thanks for the reply, It's fiber. MEO/Portugal.

The 'ifstatus wan6' returns:

{
"up": true,
"pending": false,
"available": true,
"autostart": true,
"dynamic": false,
"uptime": 223,
"l3_device": "wan",
"proto": "dhcpv6",
"device": "wan",
"updated": [
"addresses",
"routes",
"data"
],
"metric": 0,
"dns_metric": 0,
"delegation": true,
"ipv4-address": [

],
"ipv6-address": [
	{
		"address": "2001:8a0:70a6:be00:9e9d:7eff:fe51:92",
		"mask": 64,
		"preferred": 89777,
		"valid": 89777
	}
],
"ipv6-prefix": [
	
],
"ipv6-prefix-assignment": [
	
],
"route": [
	{
		"target": "2001:8a0:70a6:be00::",
		"mask": 64,
		"nexthop": "::",
		"metric": 256,
		"valid": 89777,
		"source": "::/0"
	},
	{
		"target": "2001:8a0:70a6:be00::",
		"mask": 64,
		"nexthop": "fe80::6aaa:c4ff:fe48:89af",
		"metric": 384,
		"valid": 89777,
		"source": "::/0"
	},
	{
		"target": "::",
		"mask": 0,
		"nexthop": "fe80::6aaa:c4ff:fe48:89af",
		"metric": 640,
		"valid": 1577,
		"source": "2001:8a0:70a6:be00:9e9d:7eff:fe51:92/64"
	}
],
"dns-server": [
	"2001:8a0:70a6:be00::1"
],
"dns-search": [
	
],
"neighbors": [
	
],
"inactive": {
	"ipv4-address": [
		
	],
	"ipv6-address": [
		
	],
	"route": [
		
	],
	"dns-server": [
		
	],
	"dns-search": [
		
	],
	"neighbors": [
		
	]
},
"data": {
	"passthru": "0010001200000de9000c64736c666f72756d2e6f726700170010200108a070a6be000000000000000001"
}

}

So as you said i change the config/dhcp to

config dhcp 'lan'
option interface 'lan'
option start '100'
option limit '150'
option leasetime '12h'
option dhcpv4 'server'
option dhcpv6 'relay'
option ra 'relay'
option ndp 'relay'
option ra_slaac '1'
list ra_flags 'managed-config'
list ra_flags 'other-config'

config dhcp 'wan'
option interface 'wan'
option ignore '1'
option dhcpv6 'relay'
option ra 'relay'
option ndp 'relay'
option master '1'

and now the PC can reach IPv6 outside.

Many Thanks mk24

[papagirafe]

Works like a charm for me too! Thanks for sharing

[mk24]

In some cases an ISP will grant you a prefix if you set reqprefix to a specific number (often 48 or 56) instead of "auto." Ask the ISP how they support IPv6.

[PTwrt]

I dont understand anything about IPv6

In my ISP Router i see a ::/56 Prefix IPv6, but probably its dynamic. I will try to understand if i can get that whit that setting. Thanks for the tip.

[mk24]

In a default configuration, if the ISP sends a GUA prefix "larger" than 60 (which means the number is smaller than 60, such as 56), part of the prefix will be applied to the LAN and the LAN machines should get GUAs and be able to reach the IPv6 Internet without any further configuration. GUA IPv6s are recognized by the first digit being 2 or 3. Any IPs that start with F are not routable on the Internet so you can disregard them for this purpose.

A dynamic GUA is of course not as good as static, but all that it really means is that should the ISP connection drop and re-establish with a different prefix, the network needs time to re-number itself.