Brocade Network Advisor SAN + IP User Manual v12.1.0 - Manual (Page 892)

Brocade Network Advisor SAN + IP User Manual 837
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FICON best practices for Virtual Fabrics
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- Disable Device Probing – When selected, third-party software, except for CUP, is prohibited
from managing the switch. This check box should be selected unless otherwise advised by
your switch service provider.
- Long Distance Fabric – This parameter sets E_Ports to LD mode (increases BB credits for
long distance performance). Select this check box only when ISLs between the switch and
a connected device exceed 10 Km. Dense wave division multiplexing (DWDM) equipment
usually provides BB credits, so there is typically no reason for additional BB credits unless
there are direct ISLs between switches or course wave division multiplexing (CWDM) is
being used. Long Distance Fabric requires a license.
• When configuring the logical fabric in the New Logical Fabric Template or New Logical Switch
dialog box (Switch tab), use the following parameters:
- Preferred Domain ID – Use a unique domain ID for all switches. Domain IDs are entered in
either decimal or hexadecimal. If you enter the domain ID in decimal, ensure you use the
correct hexadecimal equivalent. For example, if the first byte of the link address is 33, then
the domain ID in decimal is 51. Also, use a domain ID that is the hexadecimal equivalent of
the Switch ID in the input/output completion port (IOCP). For example, for Switch ID 1F, set
Domain ID to 31 in decimal or 1F in hexadecimal.
- Insistent – As a best practice, select this check box to not allow the domain ID to be
changed when a duplicate domain ID exists. Although an insistent domain ID is only
required when 2-byte link addressing is used on the host, setting Insistent for all
environments is the recommended best practice. Setting this parameter does not cause
any problems, but not selecting it can cause problems if 2-byte addressing is used in the
future.
• When the Logical Switch Change Conformation and Status dialog box displays after configuring
logical switches through the Logical Switches dialog box, be sure the following parameters are
selected:
- Re-Enable ports after moving them.
- Unbind Port Addresses while moving them
- QoS disable the ports while moving them.
If you do not select the Unbind Port Addresses while moving them check box, the port address
is “remembered” by the switch from where it was moved and cannot be assigned to another
port. This is rarely desired when configuring switches for FICON applications. Also, because it is
not obvious that the address is in memory, not selecting this option can cause confusion when
making future changes.
• Configure at least one logical switch and move all FICON ports to that logical switch, even if
that means moving all ports in the chassis.
• Enabling or disabling Virtual Fabrics is disruptive as it requires you to reboot the switch. If the
switch is in a production environment, make sure all channel connections to the switch have
been configured offline first.
• As a best practice, do not change a production fabric unless there is a compelling reason to do
so. For new installations, the recommended best practice is to enable Virtual Fabrics. Even if
you do not plan to use the chassis for more than a single logical switch, you have the option of
adding a logical switch in the future without an outage.