This is the rn (Relative Name), the single naming segment that, appended to its parent's dn, forms the full dn for this one instance of a DNS domain suffix configured for UCS Manager or CIMC management-network name resolution, appended to unqualified hostnames when resolving them. UCS Manager derives this segment automatically from the object's own defining attribute (such as an address, index, or configured name), so seeing a distinctive rn like this is how you tell one DnsSuffix row apart from every sibling row under the same parent. For this class the rn typically looks like 'dns-suffix-corp.example.com'.