Open Systems Tape Pipelining; Fcip Fastwrite And Tape Acceleration - Brocade Communications Systems StoreFabric SN6500B User Manual

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Open systems tape pipelining

TABLE 72
DSCP priority/bits
59 / 111011
63 / 111111
Open systems tape pipelining
Open Systems Tape Pipelining (OSTP) can be used to enhance open systems SCSI tape write I/O
performance. To implement OSTP over FCIP, you must enable the following two features:
•
•

FCIP Fastwrite and Tape Acceleration

When the FCIP link is the slowest part of the network, consider using FCIP Fastwrite and Tape Read
and Write Pipelining. FCIP Fastwrite and Tape Acceleration are two features that provide
accelerated speeds for read and write I/O over FCIP tunnels in some configurations:
•
•
Both sides of an FCIP tunnel must have matching configurations for these features to work. FCIP
Fastwrite and Tape Acceleration are enabled by turning them on during the tunnel configuration
process. They are enabled on a per-FCIP tunnel basis.
Consider the constraints described in
TABLE 73
FCIP Fastwrite
Each GbE port supports up to 2048 simultaneous
accelerated exchanges, which means a total of 2048
simultaneous exchanges combined for Fastwrite and
Tape Acceleration.
Does not natively support multiple equal-cost path
configurations. Traffic isolation zoning can be used to
support these configurations.
772
Default Mapping of DSCP priorities to L2Cos Priorities (Continued)
L2CoS priority/bits
4 / 100
0 / 000
FCIP Fastwrite and Tape Acceleration.
FC Fastwrite.
FCIP Fastwrite accelerates the SCSI write I/Os over FCIP.
Tape Acceleration accelerates SCSI read and write I/Os to sequential devices (such as tape
drives) over FCIP, which reduces the number of round-trip times needed to complete the I/O
over the IP network and speeds up the process. To use Tape Acceleration, you must also
enable FCIP Fastwrite.
OSTP constraints
Assigned to:
High QoS
-
Table 73 when configuring tunnels to use OSTP.
Tape Acceleration
Each GbE port supports up to 2048 simultaneous
accelerated exchanges, which means a total of 2048
simultaneous exchanges combined for Fastwrite and
Tape Acceleration.
Does not natively support multiple equal-cost path
configurations or multiple non-equal-cost path
configurations. Traffic isolation zoning can be used to
support these configurations.
Brocade Network Advisor SAN User Manual
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