Configurable DNS Response Size

When a realm is used for DNS queries, the Oracle® Enterprise Session Border Controller can accept UDP DNS responses configurable up to 65535 bytes.

This functionality is useful when large numbers of SRV records will be returned in a DNS query thereby eliciting a large-sized DNS response. This behavior should be configured on the realm where the DNS servers are located.

To extend the valid DNS response size, add the dns-max-response-size option to the realm configuration. If this option is not configured, the Oracle® Enterprise Session Border Controller uses the default maximum response size of 512 bytes, and information past the 512th byte will be ignored.

Do not add the dns-max-response-size option to realms where DNS queries are not being performed. Ensure that the realm where this option is configured is referenced in a transport realm's dns-realm parameter. Only the local value of the dns-max-response-size option is used for the realm; there is no inheritance of this value.