Brocade Web Tools Administrator's Guide - Supporting Fabric OS v5.3.0 (53-1000435-01, June 2007)

40 Web Tools Administrator’s Guide

Publication Number: 53-1000435-01

Changing system configuration parameters

• BB Credit

The buffer-to-buffer credit is the number of buffers available to attached devices for frame

receipt. The default BB Credit is 16. The range is 1–27.

• R_A_TOV

Resource allocation timeout value (in milliseconds). This variable works with the E_D_TOV to

determine switch actions when presented with an error condition. The default is 10000. The

possible range is 4000–120000.

• E_D_TOV

Error detect timeout value (in milliseconds). This timer is used to flag a potential error condition

when an expected response is not received within the set time. The valid range is 1000–5000.

• Datafield size

The largest possible data field size (in bytes). The valid range is 256–2112.

• Switch PID Format

Select a switch PID format from one of the following:

- Format 1 (0-base, 256 encoding)

- Format 2 (16-base, 256 encoding)

• Sequence Level Switching

Select this box to enable frames of the same sequence from a particular group to be

transmitted together. When this option is not selected, frames are transmitted interleaved

among multiple sequences. Under normal circumstances, sequence-level switching should be

disabled for better performance. However, some host adapters have issues when receiving

interleaved frames among multiple sequences.

• Disable Device Probing

Set this mode only if the switch N_Port discovery process (PLOGI, PRLI, INQUIRY) causes an

attached device to fail. When set, devices that do not register with the Name Server are not

present in the Name Server database.

• Per-Frame Routing Priority

Choose whether to select per-frame routing priority. When enabled, the virtual channel ID is

used in conjunction with a frame header to form the final virtual channel ID.

• Suppress Class F Traffic

Applies only if VC-encoded address mode is also set. When selected, translative addressing

(which allows private devices to communicate with public devices) is disabled.

• Insistent Domain ID Mode