S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
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Cisco MDS 9000 Family CLI Configuration Guide
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Chapter 28 Configuring FICON
FICON Tape Acceleration
Step 3
Issue the
no shutdown
command on each port to enable traffic flow.
Note
If you specify the
ficon swap interface
old-interface new-interface
after swap noshut
command, the ports are automatically initialized.
FICON Tape Acceleration
The sequential nature of tape devices causes each I/O operation to the tape device over an FCIP link to
incur the latency of the FCIP link. Throughput drastically decreases as the round-trip time through the
FCIP link increases, leading to longer backup windows. Also, after each I/O operation, the tape device
is idle until the next I/O arrives. Starting and stopping of the tape head reduces the lifespan of the tape,
except when I/O operations are directed to a virtual tape.
Cisco MDS SAN-OS software provides acceleration for the following FICON tape write operations:
•
The link between mainframe and native tape drives (both IBM and Sun/STK)
•
The back-end link between the VSM (Virtual Storage Management) and tape drive (Sun/STK)
FICON tape acceleration over FCIP provides the following advantages:
•
Efficiently utilizes the tape device by decreasing idle time
•
More sustained throughput as latency increases
•
Similar to FCP tape acceleration, and does not conflict with it
Note
FICON tape read acceleration over FCIP is not supported.
Figure 28-5
through
Figure 28-8
show supported configurations:
Figure 28-5
Host Directly Accessing IBM/STK (StorageTek) Library
Figure 28-6
Host Accessing Standalone IBM-VTS (Virtual Tape Server) /STK-VSM (Virtual Shared
Memory)
IBM
OS/390
Tape library
FICON
Cisco MDS
Cisco MDS
FICON over
FCIP
144880
FICON
Tape library
FICON over
FCIP
FICON over
FCIP
144881
VSM
Cisco MDS