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Bnshsysjab

Can someone let AWS know? I was annoyed to find out that lightsail does not support IPv6, in 2020...

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And Google's own cloud servers

Coming in 2021 though.

Source? That would be great news, but I can't find anything.

Don't hold your breath.

Azure officially has IPv6 support, but like every other cloud vendor, they are 100% native IPv4 with IPv6 bolted on as an afterthought.

For example, it's impossible to create an IPv6-only Azure vNet.

The metadata API endpoint is IPv4-only (169.254.169.254).

So on, and so forth...

Interestingly enough, you can now access Google services over v6 from inside GCP, but only them for now.

Excuse my ignorance, on what layer do we need IPv6 when deploying our apps/systems/whatever on AWS? Is IPv4 becoming a severe problem for such things?

Gmail blocks my mailserver, I recently discovered it’s the lack of ipv6 that causes it.

If your mail server is in AWS, it's not ipv6 that is the problem per se. It's that google has blocked the entire AWS address space. To be fair, you shouldn't be sending email from AWS without going through SES, which has it's own address space and has specific deals for deliverability to all the big mail recipients, like gmail and hotmail.

AWS allows you to switch mail servers to a specific address range which, as far as I know, are treated nicer than the regular address space.

Please provide citations if you’re going to speak so factually.

> Please provide citations if you’re going to speak so factually.

That's fair. I don't really have handy citations. I just know this stuff from working in email deliverability for a long time. I guess you can choose to believe me or not.

I have a DigitalOcean mailserver that isn’t blocked by google, or o365 ;)

I had the opposite problem.

A mailserver was blocked by Gmail until I disabled IPv6 on it.

Interesting. I imagine it may be ips sitting in a pool which are known bad in your case, and in mine known good slightly tipping the black box scales.

I just wish gmail had tech support so I could resolve this directly instead of flailing about trying random obscure solutions.

In my case, the messages from Gmail's MX suggest the problem was reverse DNS for the EHLO name returning the IPv4, for a connection from the IPv6.

I decided I'd need to configure Exim4 to issue a different EHLO name depending on whether it's connecting over IPv4 or IPv6, and then triple check (with tests) that reverse DNS unambiguously matched in each case.

But as deliverability was the priority, disabling IPv6 seemed lower risk than fiddling with config, seeing it work, then finding out a few weeks later that it introduced another "Google mystery factor". Reviewing that is on the todo list somewhere, very low priority.

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