After I reset pfSense, and did a new setup, the issue still remain. I can't connect to archlinux.org via IPv6.
@johnpoz said in Not able to connect to some website:
I would suggest he moves his lan back to 1500, and then get with his ISP for the proper setup for his wan connection.. A common pppoe mss clamp size is like 1452.. But for optimal working with his ISP he should contact them for proper setup.
I agree, I should consult my ISP for help. I left MTU and MSS default. Will it related to PMTUD no working? The last result might be using pfSense in transparent mode. I've never tested it yet.
Another issue is ICMP req always failed (tested using ipv6-test.com), even I allow it on WAN interface. This didn't happen on my last configuration, which is pretty much the same as this one except I left DHPCv6 enable. I think I disable DHCPv6 last time, MyPC use RDNSS instead. I'm scratching my head off.