ns03.webex.com has no NS records.
NS records for this zone are defined at webex.com.
NS records for this zone are defined at webex.com.
Question and response
Question
dig ns03.webex.com. NS
Answer
The response has no answer records.
Authority
webex.com. 120 SOA hns001.sjc03.webex.com. csg-ia.cisco.com. 2023904912 10800 1800 2419200 120
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0