HP StorageWorks Fabric OS 6.1.1 administrator guide (5697-0235, December 2009)

442 Configuring and monitoring FICON Extension Services
FICON emulation requirement for a determinate path
FICON emulation processing creates FICON commands and responses on extended FICON Channel Path
IDs (CHPIDs), and must know exactly what exchanges are occurring between a Channel and a control unit
(CU) on a CHPID to function correctly. For FICON Emulation processing to function correctly, the responses
to Host I/O (channel I/O) must be carried on the same ISL as the commands.
There are three ways to ensure a determinate path for FICON commands and responses:
• Define only one IP route and one FCIP tunnel between sites.
• Use a traffic isolation zone (TI zone) to ensure there is only one path across an ISL or FCIP Tunnel
between an ingress and egress FICON port.
• For Brocade M-series directors (6140 and i10K directors), implement the Allow/Prohibit feature.
One Ethernet interface, one IP route and one FCIP tunnel between sites
You can ensure a determinate path for FICON commands and responses by configuring only one Ethernet
connection between the 400 MP Router SAN routers or FR4-18i blades using only one IP route and one
FCIP tunnel.
Traffic isolation zoning
The Traffic Isolation feature may be used to control the flow of interswitch traffic through the 400 MP Router
SAN router or FR4-18i VE_Port or E_Port connections. This feature can be used with Allow/Prohibit settings
on M-series directors to create complete flow through paths between end points connected through
M-series and FOS products. Traffic isolation uses a special zone, called a traffic isolation (TI zone), to
create dedicated paths for specific traffic. You can create a TI zone from either the command line, as
described in ”Administering Advanced Zoning” on page 195, or from Web Tools.
Allow/Prohibit for M-series directors
The Allow/Prohibit feature is available on the Brocade i10k and 6140 M-series directors. This feature
enables you to control traffic flow between F_Ports and E_Ports. It is implemented from the Brocade Mi10K
or M6140 Director Element Manager GUI through use of an Allow/Prohibit matrix. The matrix allows you
to block (prohibit) specific F_Port to E_Port connections. You can create a determinate data path by
blocking all F_Port to E_Port connections except the one you want to use for FICON traffic. Figure 58 shows
a portion of the allow/prohibit matrix. The F_Port addresses are in the vertical column to the left, and the
E_Port addresses are in a horizontal row at the top. In the portion shown, F_Port address 04 can connect to
E_Port 07. All other connections are prohibited, as indicated by the universal prohibited symbol.
Figure 58 Allow/Prohibit example
See the Brocade Mi10K or M6140 Director Element Manager User Manual for specific information about
implementing the allow/prohibit feature.
FICON emulation concepts and features
FICON emulation supports FICON traffic over IP WANs using FCIP as the underlying protocol. FICON
emulation can be extended to support performance enhancements for specific applications through use of
the following licensed features.
• XRC emulation
• Tape write pipelining
• Tape read pipelining