Domain name system operations implemented using scalable virtual traffic hub

A system, comprising:

• one or more computing devices of a provider network;
• wherein the one or more computing devices include instructions that upon execution on a processor cause the one or more computing devices to:
• enable connectivity via a virtual traffic hub between a first isolated network and a second isolated network, wherein a first private address range from which respective network addresses are assigned to one or more resources of the first isolated virtual network comprises at least a first network address which is also part of a second private address range of the second isolated virtual network, wherein the virtual traffic hub comprises a plurality of layers including (a) a routing decisions layer at which a routing action for a network packet is identified and (b) an action implementation layer at which routing actions identified at the routing decisions layer are performed;
• determine, at the virtual traffic hub, that a particular domain name system (DNS) message is to include an indication of a first resource of the first isolated virtual network, wherein at the first isolated network the first resource is assigned a first network address within the first private address range, and wherein the particular DNS message is to be directed to a second resource in the second isolated network;
• obtain, at the virtual traffic hub, a transformed version of the first network address;
• and
• cause the transformed version to be included in the particular domain name system message delivered to the second resource.