spf.salesforce.com NS records

NS Authoritative DNS server
30m
spf.salesforce.com has no NS records.
NS records for this zone are defined at salesforce.com.

Question and response

Question

dig spf.salesforce.com. NS

Answer

The response has no answer records.

Authority

salesforce.com. 1800 SOA mastername.salesforce.com. hostmaster.salesforce.com. 2016652926 600 900 2592000 1800

Additional

. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0