In this paper, Forwarding Obstruction Attack, an attack on overlay networks is focused on, and Hub Node Reinforcement Method to suppress affects of forwarding obstruction is proposed. An inquiry is sent to a randomly selected nodes to receive the number of forwarding search queries. Then the node can know how often it forwards queries in comparison to other nodes. As a result, if the node realizes that it is a Hub node, it expands its routing table. By carrying out the above procedures in a dynamic network, each node determines whether it is a Hub node or not, and decreases the chances of a search query reaching a node which obstructs forwarding. Through computer simulations, the proposed method is compared with no countermeasure and equally reinforced method in the following criteria: search success rate and memory overhead. Compared to the equally reinforced method, the proposed method increases the success search rate by 10% and decreases the memory overhead of the whole network by 30% and shows that the proposed scheme is efficient in the above two criteria.