A mesh network system is provided that enables a parent node to regain communication with a child node that is unresponsive due to bad link conditions on the currently used communication channel. The parent and the unresponsive child node are configured to respond to unreachability conditions by having synchronized transmit and reception scans for signals on each available channel. Once a determination has been made that an alternate channel is available that allows communication, embodiments further provide a mechanism for determining whether to trigger a network-wide channel switch, if, for example, the node is critical to an application supported by the network.