Junos OS

Hi,

I expect this is not the right place to ask this question but thought someone may have seen a similar issue before.

I don't necessarily think that it is the CPE at fault here, but you all know the layout, I think, but here it is again from an end laptop perspective:

Laptop LAN --> CPE LAN - CPE WAN --> SRX340 --> Core --> Upstream ISP.

If I ping, for example, facebook IPv6 address from SRX340, it all works fine. If I ping facebook IPv6 from the CPE it works fine. If I try and ping from the Windows 10 laptop I cannot even ping the WAN interface on the CPE. When I complete an "ipconfig" on the Laptop, I notice that the IPv6 address given is not even in the range or derivative of the WAN assigned address.

The CPE is a Draytek Vigor 2860 and I have configured it as per their manual for IPv6.

If anyone has come across this type of error before, would be good to know how you resolved it.

Check if delegated prefix is installed for dhcp client cpe. After that you need enable slacc or dhcp server in cpe lan though I think It should be automatic.

Hi Hugleo,

As an add on, because this is the Ethernet Core side, I am manually configuring the device (as we will have to initially before they are sent out).

So, the static WAN address is a /126 so that it can have the same prefix as the SRX340 CPE Facing interface. As I mentioned, if I ping any internet address from the WAN of the CPE it is all working perfectly. So, I looked up the draytek IPv6 LAN config page here:

https://www.draytek.com/?a=resource/update&action=post/update&id=1880

Which seems to involve PD but then, I don't normally deal with the CPE end points. The guy that does is back tomorrow so maybe he knows.

There is an entry area where I have defined the /56 and then CPE should automatically assign the /64s from this /56 as per the DHCPv6-PD auto config on the CPE. But, as I mentioned, it is assigning some strange, unknow address range.... hence why the laptop cannot communicate with the outside World... 😞

As always. after a little investigation I have found a little more information.

The laptop has several "preferred" addresses, of which one of them (from a wireshark trace) is the one it is using and it is an old address. Now just need to figure out how to clear these addresses and use the new one.

I cleared the preferred addresses and set DHCPv6 but the laptop is not getting an address from the DHCPv6 enabled Draytek CPE.

As I can ping everywhere on the internet from the CPE WAN interface, then it proves the working SRX340. So, I can close this as resolved from that perspective. I shall work on with the CPE.

Thanks