Latency Guideline; Packet Loss Guideline; Storage Application Guideline - Brocade Communications Systems 1606 Administrator's Manual

The following port blades are not supported in a FICON environment unless otherwise noted:
In an Admin Domain-enabled fabric, you should put all of the ports on the FC4-48, FC8-48, FC8-64,
and FC4-16IP blades in an Admin Domain other than the one used for FICON ports. The ports on
these blades should not belong to the zone in which FICON devices are present.
In all switches and directors that have FICON devices attached, or where FICON traffic will be
carried, the port-based routing policy is required (set aptPolicy option 1) unless Lossless is
specified. Exchange based routing (set aptPolicy option 3) is only supported when Lossless is
specified.

Latency guideline

The maximum allowable network roundtrip latency is typically 200 ms. This is application
dependent, and for some applications it may be lower. For synchronous mirroring applications, the
maximum latency is typically less than 10 ms. These values are to maintain data throughput
performance. However, many synchronous applications can run in asynchronous mode, allowing
more than one outstanding I/O per transaction.

Packet loss guideline

The end-to-end network should maintain less than one percent packet loss for optimum
performance. Performance degradation is exponential as packet loss increases above one percent.
It is highly recommended that you obtain an SLA (Service Level Agreement) with your network
provider that reflects this requirement.

Storage application guideline

Storage applications will operate more efficiently if they are tuned to match the outstanding
amount of data to the characteristics of the IP connection, such that there is always data being
transmitted. Generally speaking, with higher latency and higher bandwidth, more data can exist in
the WAN network.
FICON Administrator's Guide
53-1001771-01
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Brocade 48000 director (FC4-16, FC4-32 port blades, FR4-18i FCIP blade and FC10-6 10
Gbps port blade for ISL connections).
•
Brocade 4100, 4900, 5000, 5100, and 5300 switches.
•
The Brocade 7500 and 7800 Extension Switches and Brocade the FR4-18i (for the
Brocade 48000, DCX, and DCX-4S) and FX8-24 blade (for the Brocade DCX and DCX-4S)
provide FICON over IP extension.
•
The Brocade DCX and DCX-4S Backbones, Brocade 5100 and 5300 switches can perform
CUP operations to and from the M6140 and the Mi10K EOS-based chassis and vice-versa.
•
FC4-16IP
•
FCOE10-24
•
FS8-18
•
FC4-48
•
FC8-48 (Supported in Brocade native mode (InteropMode = 0). In the DCX, the FC8-48
blade is only supported in a logical switch defined for zero-based addressing. Not
supported on the Brocade 48000.)
•
FC8-64
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FICON overview
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