EDNS Buffer Size Changing to 512 Bytes

Summary As of November 15th, 2018 our DNS resolvers (both staging and production) advertise an EDNS reassembly buffer size of 512 bytes. This change should not require any adjustment by subscribers. Background Previously we shared our initial thoughts on a potential mitigation to help defend against DNS fragmentation attacks. By reducing the maximum size of responses we’re willing to accept over U

[halfrack]

DNS での IP fragmentation attack への対策とのこと。 unbound なのか。 TCP 開けようね。