smtp-06e7821ceadef912c.core1.sfdc-yfeipo.mta.salesforce.com has no NS records.
NS records for this zone are defined at sfdc-yfeipo.mta.salesforce.com.
NS records for this zone are defined at sfdc-yfeipo.mta.salesforce.com.
Question and response
Question
dig smtp-06e7821ceadef912c.core1.sfdc-yfeipo.mta.salesforce.com. NS
Answer
The response has no answer records.
Authority
sfdc-yfeipo.mta.salesforce.com. 1800 SOA dns01.salesforce.com. hostmaster.salesforce.com. 2020072610 1800 900 2592000 1800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0