2.4.1. SvcPriority

2.4.1. SvcPriority

When SvcPriority is 0, the SVCB record is in AliasMode (Section 2.4.2). Otherwise, it is in ServiceMode (Section 2.4.3).

Within a SVCB RRset, all RRs SHOULD have the same mode. If an RRset contains a record in AliasMode, the recipient MUST ignore any ServiceMode records in the set.

RRsets are explicitly unordered collections, so the SvcPriority field is used to impose an ordering on SVCB RRs. A smaller SvcPriority indicates that the domain owner recommends the use of this record over ServiceMode RRs with a larger SvcPriority value.

When receiving an RRset containing multiple SVCB records with the same SvcPriority value, clients SHOULD apply a random shuffle within a priority level to the records before using them, to ensure uniform load balancing.