Dell PowerVault 51F (8P Fibre Channel Switch) - Manual (Page 72)

4-10 Dell PowerVault 51F 8-Port Fibre Channel Switch Installation and Troubleshooting Guide
A listing of the configurable fabric parameters is shown in Table 4-5.
Table 4-5. Fabric Parameters
Field Description
Domain The domain number uniquely identifies the switch in a fabric and
may be any value between 1 and 239. Normally, this value is
automatically assigned by the fabric.
BB credit The buffer-to-buffer (BB) credit represents the number of buffers,
in a range from 1 to 16, available to the host. For a complete
description of this value, refer to the industry specification Fibre
Channel Physical and Signaling Interface (FC-PH).
R_A_TOV The Resource Allocation Time Out Value (R_A_TOV) is displayed
in milliseconds. This variable works with the variable E_D_TOV to
determine the switch's actions when presented with an error
condition.
Allocated circuit resources with detected errors are not released
until the time out value has expired. If the condition is resolved
prior to the time out, the internal time out clock resets and waits
for the next error condition.
E_D_TOV Error Detect Time Out Value (E_D_TOV) is displayed in millisec-
onds. This timer is used to flag a potential error condition when
an expected response is not received (an acknowledgment or
reply in response to packet receipt, for example) within the set
time limit. If the time for an expected response exceeds the set
value, then an error condition is met.
Data field size This 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
field to a value smaller than 2112 may result in decreased
performance.
Non-SCSI
Tachyon Mode When set, multiple sequences from different sources are inter-
leaved to Tachyon-based controllers at sequence boundaries
rather than at frame boundaries, resulting in better performance
from Tachyon-based controllers. Set this mode when there are
no Tachyon-based SCSI host adapters connected to the fabric.
Disable
Device
Probing When this is set, devices that do not register themselves 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 pro-
cess (PLOGI, PRLI, INQUIRY) causes some attached device to
fail.