AbstractWe consider anNduplicate-server system, where each server consists of two reconfigurable duplicated units which are subject to breakdowns. This system is studied analytically using generating-functions, and also numerically using the matrix-geometric procedure. Using the generating-function approach we obtain a recursive expression of the queue-length probability distribution forN= 1. This expression is difficult to generalize toN⩾2. The numerical method is applicable for any value ofN. For anyN, we also obtain the condition for stability and the availability of the system.