DNS/1/EDNS/broken serversについて、ここに記述してください。
Removing EDNS Workarounds
- DNS-OARC 28, San Juan, PR 9. March 2018
Background
EDNS standard (RFC 2671, 1999; updated by RFC 6891)
DNS software vendors added various workarounds for broken servers
Broken servers:
- Doesn’t respond at all
- Respond with non-FORMERR error code
1. 計画
Retry on error with EDNS again unless FORMERR is received