Checking a Zone for Corrupted Entries
If you get a “CNAME and other data” or “multiple RRs of singleton type” error message on Zone Transfer or systemd service restart, you can attempt to find the corrupted entries by doing the following commands on the console.
dig axfr example.com @nameserver > tmp
named-checkzone example.com tmp
# OR
dig @nameserver dnszonename axfr > tmp
named-checkzone dnszonename tmp
Example Output of named-checkzone:
dns_master_load: tmp:15: entry.dnszonename: CNAME and other data
zone dnszonename/IN: loading from master file tmp failed: CNAME and other data
zone dnszonename/IN: not loaded due to errors.