Brocade Access Gateway Administrator's Guide (53-1000605-01, October 2007)

Access Gateway Administrator’s Guide 7
53-1000605-01
Access Gateway policies
1
a. The host sends a FLOGI (fabric login) request.
b. Access Gateway converts the FLOGI request into an FDISC request to the fabric with the
same parameters as the host.
c. The fabric processes the request and sends an FDISC response.
d. Access Gateway converts the FDISC ACC response to the host as an FLOGI ACC using the
same parameters as the fabric.
e. The host receives the response from the fabric.
After ports are initialized, Access Gateway becomes logically transparent to the host and
the fabric, as shown in Figure 4.
FIGURE 4 Host log in request
Access Gateway policies
Access Gateway has four policies available to help you configure and maintain your Access
Gateway environment. The policies listed below are detailed later in this section.
• Path Failover policy enables hosts to automatically remap to an online N_Port within a port
group if the N_Port they are connected to goes offline.
• Failback policy automatically reroutes the F_Ports back to the originally mapped N_Ports if
within a port group as those N_Ports come back online.
• Port Grouping (PG) policy allows you to restrict Failover and Failback to a set of related
N_Ports.
• Automatic Port Configuration (APC) policy enables the switch to automatically detect ports
coming online and enforces a balance ratio of F_Ports to N_Ports.
Path Failover policy
The Brocade Access Gateway Path Failover policy allows hosts to automatically remap to an online
N_Port if the primary N_Port goes offline. The Path Failover policy evenly distributes the F_Ports
that are mapped to an offline N_Port among all the online N_Ports. The Path Failover policy is a
parameter of each N_Port. By default, the Path Failover policy is enabled for all N_Ports.
The following sequence describes how a failover event occurs:
1. An N_Port goes offline.
2. All F_Ports mapped to that N_Port are disabled.
a
b
c
d
e