Hi,
I thought I had this problem worked out but it appears not. For example, trying to browse to ipv6-test.com does not respond...
So, here is the topology again:
Laptop (windows 10) --> CPE --> LNS --> Core --> Upstream ISP
IPv4 is working great. I have the CPE configured to 1500 MTU and the tunnel profile on the LNS is configured to 1500 as per below:
set access group-profile l2tp-group-profile ppp ppp-options mtu 1500
If I ping www.ipv6-test.com on 2001:41d0:8:e8ad::1 from the laptop it works fine. If I tracert from the laptop to this IPv6 address, it also works fine and takes the correct route. However, when I try and browse to the website it fails completely. I get nothing in return.
So, the MSS is configured on the upstream interface (egress) as per below:
set interfaces xe-1/2/5 unit 0 family inet6 tcp-mss 1410
Strangely, if I complete a wireshark trace while connecting, the TCP SYN from the laptop to the URL does not state any MSS but the SYN ACK response states 1440 from the server. I am completing the wireshark trace on the actual laptop but I expected to see a TCP SYN with an MSS of 1410 and agreement on this in the SYN ACK from the URL. This is not the case.
So, couple of questions please:
1: Does the LNS require any specific MTU setting on the PPP interface for IPv6?
2: Anyone else seen this issue and know how to resolve it?
Thanks