An apparatus includes at least one first input/output (I/O) module having multiple first I/O channels. Each first I/O channel is configured to provide a communication path. The apparatus also includes a second I/O module having multiple second I/O channels. Each second I/O channel is configured to provide a redundant communication path for one of the first I/O channels. The apparatus is configured to provide the redundant communication paths for only a subset of the first I/O channels. The first I/O channels may include critical I/O channels and non-critical I/O channels, and the apparatus may be configured to provide the redundant communication paths for only the critical I/O channels. The apparatus can be configured to provide the redundant communication paths for the first I/O channels of a single first I/O module or multiple first I/O modules.