Golang net: go DNS resolver fails to connect to local DNS server [1.21 backport]

@ianlancetaylor requested issue #67925 to be considered for backport to the next 1.21 minor release.

@gopherbot Please open backport issues.

The Go DNS resolver doesn't work with at least one DNS server that apparently does not handle EDNS0 additional headers correctly. The fix is to add a new GODEBUG setting. Requesting a backport to add the GODEBUG setting to earlier releases.

Comment From: gabyhelp

Similar Issues

• https://github.com/golang/go/issues/67934
• https://github.com/golang/go/issues/29700
• https://github.com/golang/go/issues/51161

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Comment From: gopherbot

Change https://go.dev/cl/592235 mentions this issue: [release-branch.go1.21] net: add GODEBUG=netedns0=0 to disable sending EDNS0 header

Comment From: gopherbot

Closed by merging 74ac37e9da31d6ab37575e7f2d7287fbb6b168d9 to release-branch.go1.21.