Network OS Administration Guide

Supporting Network OS 6.0.1a

Part Number: 53-1003768-04

Network diagrams

The following diagrams illustrate various connection configurations among switches and network elements, with and without Access Gateway.

The following figure illustrates the connection of eight hosts through an AG switch to a Fibre Channel fabric edge switch.
Figure 31. Hosts connecting to FC fabric through switch in AG mode
An AG switch can connect to only one Fibre Channel SAN. Ports on this switch connecting to a second FC SAN are disabled. Multiple AG switches, each belonging to a different VCS cluster, can connect to the same SAN fabric.
The following figure illustrates an alternate connection of hosts (servers) to an FC fabric through a switch not in Access Gateway mode. A VDX FC port, configured as an E_Port, connects to the FC SAN through an ISL connection to an FC router. For more information on configuring FC ports for an ISL and FC router connection, refer to Configuring Fibre Channel Ports.
Figure 32. Connecting Network OS fabric to FC fabric without AG mode

Switches in AG mode are logically transparent to the host and the fabric. Therefore, you can increase the number of hosts that have access to the fabric without increasing the number of switch domains. This simplifies configuration and management in a large fabric by reducing the number of domain IDs and ports.

VCS mode must be enabled to enable Access Gateway on the switch. By default, both VCS mode and AG are enabled.

While in AG mode, the switch functions both as a VCS and AG switch as follows:
  • It supports N_Ports, VF_Ports, and Layer 2 interfaces.
  • It can connect devices to a VCS fabric through Ethernet ports. VCS fabric services run on Ethernet ports which function under the "native" VCS switch configuration.
  • It can connect hosts to a Fibre Channel switch through VF_Ports mapped to N_Ports.
In this document, VCS native (or native) mode refers to a switch enabled in VCS mode. Access Gateway mode (or AG switch) refers to a switch in VCS mode enabled for the Access Gateway feature.
The following figure illustrates the connection of FCoE hosts to two AG switches in a top-of-rack configuration. N_Ports on these switches connect to F_Ports on Brocade DCX Backbones in the FC SAN. In addition, Layer 2 interfaces on these switches connect to other VDX switches in the VCS fabric cluster.
Figure 33. Using Access Gateway to connect FC and VCS fabrics