Multiple-master DNS system

摘要

One or more embodiments provide a system and method for DNS that is resistant to losses of network connections. In some particular embodiments, DNS servers are operated to maintain consistency of DNS records between the multiple master servers in response to connection failure. Each master DNS server monitors network connectivity by periodically testing network connections of the master server (e.g., to other master servers) to determine whether the master DNS is isolated in a manner that prevents updates from being distributed between the master DNS servers. In response to detecting network isolation of the master DNS server, the master DNS server is configured to enter the isolation mode, in which the master DNS monitors the status of connections and takes appropriate actions to update and/or recover DNS data when connections are restored.

主权项

1. A method for operating a domain name system (DNS) in a Voice-over-Internet Protocol (VoIP) call routing system, the DNS including at least two DNS servers in a multi-master configuration that provides dynamic DNS call routing information for setup of a VoIP call, the method comprising, at a first master DNS server of the at least two DNS servers:
updating DNS data records between the first master DNS server and a second master DNS server of the at least two DNS servers; monitoring for network isolation of the first master DNS server relative to at least one wide area network; entering an isolation mode in response to detecting network isolation of the first master DNS server of the at least two DNS servers, the isolation mode defining rules for a plurality of DNS zones; monitoring, while in the isolation mode, for network connectivity of the first master DNS server relative to the wide area network, wherein the steps of monitoring include attempting to access a plurality of remote websites; exiting the isolation mode in response to detecting network connectivity of the first master DNS server relative to the wide area network; updating, in response to exiting the isolation mode and to the rules for the plurality of DNS zones, DNS data records at the first master DNS server and for a first set of DNS zones using data from the second master DNS server of the least two DNS servers; at the first master DNS server, processing DNS update requests received in the first set of DNS zones; and at the second master DNS server, processing DNS update requests received in a second of the plurality of DNS zones.