Proposal to change the order of .well-known and SRV discovery techniques

proposals/1831-srv-after-wellknown.md

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+# Proposal to do SRV lookups after .well-known to discover homeservers
+
+Currently there is a logistical error proposed by [MSC1708](https://github.com/matrix-org/matrix-doc/pull/1708)
+which results in some homeservers unable to migrate to the new functionality
+proposed by [MSC1711](https://github.com/matrix-org/matrix-doc/pull/1711). This
+can happen if the delegated homeserver cannot obtain a valid TLS certificate for
+the top level domain, and an SRV record is used for backwards compatibility reasons.
+
+## Proposal
+
+We change the order of operations to perform a .well-known lookup before falling
+back to resolving the SRV record. This allows for domains to delegate to other
+hostnames and maintains backwards compatibility with older homeservers.
+
+## Tradeoffs
+
+More HTTP hits will be made due to the .well-known lookup being first. This is
+somewhat mitigated by servers caching the responses appropriately, and using
+connection pools where possible.