Configurable DNS Response Size

When a realm is used for DNS queries, the Oracle Communications 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 Communications 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.