Brocade Access Gateway Administrator's Guide Supporting Fabric OS v7.0.0 (53-1002156-01, April 2011)

Access Gateway Administrator’s Guide 35
53-1002156-01
Port Grouping policy
3
Access Gateway configuration has been restored to factory default
6. Enter the switchEnable command to enable the switch.
Automatic Port Configuration policy considerations
Following are the considerations for the Automatic Port Configuration (APC) policy:
• The APC and the PG policies cannot be enabled at the same time. You can still benefit from the
automatic port mapping feature of the APC policy when the Port Grouping policy is enabled by
enabling the auto distribution feature for each port group.
• You cannot manually configure port mapping when the APC policy is enabled.
• The APC policy applies to all ports on the switch. Enabling the APC policy is disruptive and
erases all existing port mappings. Therefore, before enabling the APC policy, you should
disable the AG module. When you disable the APC policy, the N_Port configuration and the port
mapping revert back to the default factory configurations for that platform. It is recommended
that before you either disable or enable APC policy, you save the current configuration file
using the configUpload command in case you need this configuration again.
Upgrade and downgrade considerations for the APC policy
You can downgrade to a Fabric OS level that supports the APC policy. If you upgrade from Fabric OS
v6.3.0 to Fabric OS v7.0.0, the policy that was enabled in Fabric OS v6.3.0 will be maintained.
Port Grouping policy
Use the Port Grouping (PG) policy to partition the fabric, host, or target ports within an AG-enabled
module into independently operated groups. Use the PG policy in the following situations:
• When connecting the AG module to multiple physical or virtual fabrics.
• When you want to isolate specific hosts to specific fabric ports for performance, security, or
other reasons.
How port groups work
Create port groups using the ag --pgcreate command. This command groups N_Ports together as
“port groups.” By default, any F_Ports mapped to the N_Ports belonging to a port group will
become members of that port group. Port grouping fundamentally restricts failover of F_Ports to
the N_Ports that belong to that group. For this reason, an N_Port cannot be member of two port
groups. The default PG0 group contains all N_Ports that do not belong to any other port groups.
Figure 8 shows that if you have created port groups and then an N_Port goes offline, the F_Ports
being routed through that port will fail over to any of the N_Ports that are part of that port group
and are currently online. For example, if N_Port 4 goes offline, then F_Ports 7 and 8 are routed
through to N_Port 3 as long as N_Port 3 is online because both N_Ports 3 and 4 belong to the
same port group, PG2. If no active N_Ports are available, the F_Ports are disabled. The F_Ports
belonging to a port group do not fail over to N_Ports belonging to another port group.