Patent ID: 7567582

Claim:
In a computing network system that includes a local Domain Name Service (DNS) server connected to one or more local clients or resources at a local branch office in an enterprise network, wherein the local DNS server comprises both a local temporary DNS cache and a local persistent DNS cache, a method of maintaining, in the local persistent DNS cache of the local DNS server, records that can be used to resolve IP addresses for host names of the one or more local clients or resources, wherein resolving the IP addresses for the host names of the one or more local clients or resources occurs at the local DNS server, the method comprising: the local DNS server advertising to the one or more local clients or resources that the DNS server is authoritative; the local DNS server receiving local DNS record information from the one or more local clients or resources, wherein the local DNS record information comprises information to resolve the IP addresses for the host names of the one or more local clients or resources; the local DNS server storing the local DNS record information in the local persistent DNS cache that is maintained by the local DNS server, wherein storing the local DNS record information in the local persistent DNS cache may be performed selectively or non-selectively, and wherein the local persistent DNS cache provides persistent local access to the local DNS record information, such that in the event of a power outage coupled with a loss of connection between the branch office and the enterprise hub DNS server, the local DNS information records that are stored in the local persistent DNS cache remain accessible to the local clients and can be used for IP address resolution even while the branch office is disconnected from the enterprise hub DNS server; and the local DNS server attempting to forward the local DNS record information to an enterprise hub DNS server.