SSSD trying to resolve SRV record of _KERBEROS._udp.domain.example.com' results in SRV query failed [4]: Domain name not found

Issue

• Slow performance reported for automount maps and LDAP queries using SSSD.

• The SSSD log /etc/sssd/sssd_<realm>.example.com.log reports failures during SRV resolution in DNS.

  (2022-07-19  1:48:29): [be[domain.example.com]] [collapse_srv_lookup] (0x0100): Need to refresh SRV lookup for domain domain.example.com
  (2022-07-19  1:48:29): [be[domain.example.com]] [resolv_getsrv_send] (0x0100): Trying to resolve SRV record of '_KERBEROS._udp.DOMAIN._sites.domain.example.com'
  (2022-07-19  1:48:29): [be[domain.example.com]] [resolv_discover_srv_done] (0x0040): SRV query failed [4]: Domain name not found