Domain name service method and system and storage medium

The invention provides a domain name service method and system and a storage medium, and relates to the technical field of networks. The domain name service method disclosed by the invention comprises the following steps: under the condition that an in-province domain name server fails, configuring a standby domain name service subsystem into the condition that the address of an exit router of the standby domain name service subsystem is the same as that of an exit router of the in-province domain name server, establishing a tunnel between an exit router of the standby domain name service subsystem and an exit router of the in-province domain name server; the exit router of the in-province domain name server sends the received query request to the exit router of the standby domain name service subsystem through a tunnel; and the standby domain name service subsystem feeds back the feedback information to an exit router of the provincial domain name server through a tunnel so as to forward the feedback informa