A method includes transitioning a device in an industrial process control and automation system from a secondary role to a primary role during a switchover and, in response to the switchover, clearing one or more security values stored by the device. The method also includes receiving a message at the device from a network node and, in response to determining that no security association is associated with the received message or the network node, exchanging security credentials and establishing a trust relationship with the network node. Transitioning the device includes assuming a network address of another device that previously operated in the primary role, that previously communicated with the network node, and that previously had a security association with the network node. Clearing the security value(s) can prevent the device from having the trust relationship associated with the network node when the device receives the message from the network node.