cross-posted from: https://lemmy.world/post/224140
My home ISP does CGNAT for IPv4, but provides native IPv6. I can use IPv6 just fine to access most of my resources, except for one specific server. I can access the server over IPv4 from my home network, and either over v4 or v6 from other networks I’ve tried. But I can’t access it over IPv6 from my home network.
What could be the problem here? Where do I begin to diagnose it
How far does a traceroute get you? That could help isolate where the issue may be.
I’ve looked at one, but all that I can tell is I stop reaching things somewhere between my ISP and the datacenter the server is in.
I kinda think it may be on the isp then, maybe a v6 routing issue? You could work around with an ipv4 tunnel, then route ipv6 through it. If that’s possible, I’ve never done it haha.
Yeah, ISP-related issue is all I can think of. I can connect to the server over v4 no problem, but the broken v6 connectivity to this particular endpoint is strange and nothing I’ve seen before…
I bet they get less reports on ipv6 issues than with ipv4. I have definitely seen carriers have ipv4 routing issues in enterprise networking.
Can you test that site from someone else’s ISP, and from someone else near you on the same ISP?
From other ISPs it works fine. I haven’t checked from someone else using the same ISP, but that’s a good idea. Thanks!
Check your ip address config on the destination server. Does it have a public ipv6 address assigned? Does your server routing table have a default route for that ipv6 network? Does your firewall only allow ipv4?
Yes, I can reach the IPv6 on the server from other networks. I don’t think it’s a firewall issue.
