CGN (carrier-grade net address translation) single board fault informing method and device

An embodiment of the invention provides a CGN (carrier-grade net address translation) single board fault informing method and device. The method comprises steps as follows: the method is applied to an LSN (large scale NAT (network address translation)) centralized deployment network; first CGN equipment sends fault indication to CR (core router) when detecting that a CGN single board of the first CGN equipment breaks down, so that CR switches flow to second CGN equipment. According to the CGN single board fault informing method and device provided by the embodiment of the invention, timely response to the CGN single board fault is realized, the business service quality is guaranteed, and the network maintenance cost is saved.