Outbound IPv6 in Cloudfare Workers

Developers Workers
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Hello. Does Cloudflare Workers support outbound ipv6? I am assuming it supports inbound ipv6.

Thanks in advance.

Reg

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Yes, it supports IPv4 and IPv6.

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I have done some digging and I don’t believe that IPv6 outbound is supported.

I did a straightforward node.js fetch of several IPv6 websites (via their IPv6 address, obviously) from inside a new worker and got “network unreachable”. These sites are easily reachable from my desktop computer which has IPv6 enabled.

As far as I can tell, IPv6 outbound is not available from inside Cloudflare Workers.

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What sites did you test? If you’re trying to fetch a raw IP address, that is never supported within Workers.

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Kian, you are right! It is very odd to me that you can’t fetch an IP if there’s a valid web server running on it, but it worked once I created a canonical name. To ascertain this, I created an IPv6-only website at https://ipv6test.regnatarajan.com.

There is some very inconsistent behaviour here. My findings:

A raw IPv4 address in the development environment (push send) works.
A raw IPv4 address in the production environment (surf to x.workers.dev) fails.

A raw IPv6 address in the development environment (push send) fails.
A raw IPv6 address in the production environment (surf to x.workers.dev) fails.

A CNAME on IPv6 only in the development environment (push send) fails.
A CNAME on IPv6 only in the production environment (surf to x.workers.dev) works.

I’m not sure this is usable for me. I do need to work with IP addresses directly for my project. It is, however, definitely the case that, at least in come cases, Cloudflare Workers supports outbound IPv6.

Appreciate the help.

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