1. A method for utilizing failover mechanisms for fault tolerance of a mobile traffic management service, the method comprising: responsive to detecting, at a mobile device, a failed attempt to connect to a first redundant machine in a proxy server for providing mobile traffic management service that includes optimization of traffic to and from the mobile device, the proxy server is a single entity that resides in a computer and including redundant clustered machines that share a common repository for storing subscription information for mobile devices, determining whether the proxy server is reachable; and in response to determining that the proxy server is reachable, initiating, from a mobile device, a failover process by reconfiguring the mobile device's DNS routing rules to direct the mobile device to connect to a second redundant machine in the proxy server, wherein the second redundant machine uses the subscriber information that was stored in the common repository by the first redundant machine.