Question and response
Question
dig _spf.protonmail.ch. TXT
Answer
_spf.protonmail.ch. 1200 TXT "v=spf1 ip4:185.70.40.0/24 ip4:185.70.41.0/24 ip4:185.70.43.0/24 ip4:79.135.106.0/24 ip4:79.135.107.0/24 ip4:109.224.244.0/24 include:_spf2.protonmail.ch ~all"
Authority
protonmail.ch. 1200 NS ns2.protonmail.ch.
protonmail.ch. 1200 NS ns1.protonmail.ch.
protonmail.ch. 1200 NS ns3.protonmail.ch.
Additional
ns1.protonmail.ch. 1200 A 185.70.42.150
ns2.protonmail.ch. 1200 A 176.119.200.150
ns3.protonmail.ch. 1200 A 205.132.47.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0