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Comment by runlevel1 | Hacker News Reader

mDNS is an interesting choice for service discovery. Neat idea for local development, but probably not great in production.

I believe most cloud providers don't support multicast, meaning mDNS would not work there. It's also quite slow and/or very chatty in large networks.

Looks there is support for other service discovery mechanisms via plugins, though.

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Ah, multicast such a great idea, and so hard to use at scale.

For wiw multicast/mDNS works fine on top of ZeroTier.

Although, if the underlying network doesn't, I assume you get a lot of overhead (ie: it probably wouldn't be very beneficial to try and share a video stream via multicast on top of ZeroTier on top of a network without multicast support).

mDNS is intented for local development, not production usage. It simply enables one to develop without installing a more production-worthy solution like Consul.

Oh, yeah...that is probably limiting. A quick scan seems to show Digital Ocean specifically drops multicast, and AWS/GCP/Azure have varying levels of "unsupported".

Would it work with Flannel/Calico, etc? Inefficient, but probably okay since it would be just service resolution.

Edit: Looks like no for Calico, Yes for recent Flannel, but Weave Works is probably a better choice, designed to support it from the start.

mDNS is only for local development. You can use a variety of tools such as Consul. Check out micro.mu for more info :)

Ahh. Might be a good update for the linked page.

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