Disclosed herein are techniques for maintaining a secure environment on a server. In one embodiment, the server includes a baseboard management controller (BMC), a first Ethernet port coupled with an adapter device network comprising a plurality of adapter devices, and a master adapter device including a second Ethernet port and a network switch, the network switch being controllable to be selectively coupled with at least one of the BMC, the first Ethernet port, or the second Ethernet port. The master adapter device may receive a network packet from at least one of: the first Ethernet port, the second Ethernet port, or the BMC, and determine, based on a forwarding policy, whether to forward the network packet. Based on a determination to forward the network packet, the master adapter device may determine a destination, and control the network switch to transmit the network packet to the destination.