HP StorageWorks 2/16V Brocade Fabric OS Command Reference Manual - Supporting - Page 134

2 configure The R_A_TOV, E_D_TOV, WAN_TOV, and MAX_HOPS configuration parameters are inter-related. Assigning a specific value to one or more of these parameters can change the range of allowed values that can be assigned to the other parameters. As a result, the user might not be able to set all the values within the range displayed against each parameter. To reduce problems, the configuration utility validates the modified parameter values and prompts the user to re-enter some values, if the validation check fails. Data Field Size The data field size specifies the largest possible value, in bytes, for the size of a type 1(data) frame. The switch advertises this value to other switches in the fabric during construction of the fabric as well as to other devices when they connect to the fabric. Setting this to a value smaller than 2112 might result in decreased performance. Sequence-Level Switching When sequence-level switching is set to 1, frames of the same sequence from a particular source are transmitted as a group. When this feature is set to 0, frames are transmitted interleaved among multiple sequences. Under normal conditions, sequence-level switching should be disabled for better performance. However, some host adapters have performance issues when receiving interleaved frames from multiple sequences. When there are such devices attached to the fabric, sequence-level switching should be enabled. Disable Device Probing When disable device probing is set to 1, devices that do not register with the Name Server will not be present in the Name Server data base. Set this mode only if the switch's N_Port discovery process (PLOGI, PRLI, INQUIRY) causes an attached device to fail. Suppress Class F Traffic By default, the switch can send Class F frames. When this option is turned on, Class F traffic is converted to Class 2 traffic before being transmitted. Switch PID Format The formats are as follows: 0 Native PID Format (16 based, 16 port format), for fabrics with legacy low-count port switches. 1 Core PID Format (0 based, 256 port format), preferred mode for mixed fabrics with legacy and new switches. 2 Extended Edge PID Format (16 based, 256 port format), used in mixed fabrics with legacy and new switches to avoid the need to reboot host systems when static PID binded is used. Per-frame Route Priority In addition to the eight virtual channels used in frame routing priority, support is also available for per-frame-based prioritization when this value is set. When Per-frame Route Priority is set to 1, the virtual channel ID is used in conjunction with a frame header to form the final virtual channel ID. Long Distance Fabric When this mode is set to 1, ISLs in a fabric can be up to 100 km long. The exact distance level is determined by the per-port configuration on the E_Ports of each ISL. Both E_Ports in an ISL must be configured to run the same long-distance level; otherwise, the fabric will be segmented. 102 Fabric OS Command Reference Manual 53-1000436-01