Deployment Guide

1. Connect to the switch and log in using an account assigned to the admin role.
2. Enter the portCfgEPortCredits --enable command to allocate credits to an E_Port. In the following
example, 14 credits are allocated to each of the medium Virtual Channels (VCs) for non-QoS ports,
and to both the medium and high VCs for QoS ports.
switch:admin> portcfgeportcredits --enable 12/6 14
Success
3. Enter the portCfgEPortCredits --show command to verify that the credits have been allocated to
the E_Port. In the following example, it is verified that 14 credits per VC have been allocated to the
E_Port.
switch:admin> portcfgeportcredits --show 12/6
E-Port Credit Configured : 14
Success.
Buffer credit recovery
Buffer credit recovery allows links to recover after buffer credits are lost when the buffer credit recovery
logic is enabled. The buffer credit recovery feature also maintains performance. If a credit is lost, a
recovery attempt is initiated. During link reset, the frame and credit loss counters are reset without
performance degradation.
Credit recovery is supported on E_Ports, F_Ports, and EX_Ports.
Buffer credit recovery is enabled automatically across any long-distance connection for which the
E_Port, F_Port, or EX_Port buffer credit recovery mechanism is supported. For 16-Gbps FC devices
and blades (Brocade 6505, 6510, 6520, M6505, 6547, CR16-4, CR16-8, FC8-32E, FC8-48E, FC16-32,
FC16-48, FC16-64), you can use the portCfgCreditRecovery command to disable or enable buffer
credit recovery on a port.
Buffer credit recovery over an E_Port
To support buffer credit recovery, E_Ports must be connected between devices that support 16 Gbps or
between devices that support 8 Gbps.
• Devices that support 16 Gbps:
‐ Brocade 6505, 6510, 6520, M6505, 6547
‐ FC8-32E, FC8-48E,FC16-32, FC16-48, FC16-64
• Devices that support 8 Gbps:
‐ Brocade 300, 5100, 5300, 5410, 5424, 5450, 5480, VA-40FC
‐ FC8-16, FC8-32, FC8-48
If a device that supports 16 Gbps is connected to a device that supports only 8 Gbps, buffer credit
recovery is disabled, even if both devices are running 8 Gbps.
The buffer credit recovery feature for E_Ports is enabled for the following flow-control modes:
• Normal (R_RDY)
• Virtual Channel (VC_RDY)
• Extended VC (EXT_VC_RDY)
Buffer credit recovery
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