Chapter 2. Hardware 53
q We also recommend that you do not use the HMC as the ESCON Director console. We do
recommend using the same PC to act as the console for both the ESCON Directors and
the Sysplex Timers. There should be one console close to the Directors, for the service
representative to use while working on the Directors. There should also be a console in
the operator’s bridge area, so the operators can watch for errors or alerts.
The ESCON Director console is not required for continuous operation of the Directors, nor is
it required to recover after a Director is powered off/on. One matrix configuration file, the IPL
file, is stored in the CTP card. If defaults are accepted (Active = Saved option selected), this
file will be the most recently activated matrix configuration. After power off/on, the Director
operation will be restored and the matrix configuration stored in the CTP card will be active.
q We recommend that the Director console should always be available in order to:
Maintain copies of matrix configuration files.
Provide error reporting and log functions.
Provide current status of the entire Director network.
The console is not required for activating matrix configuration changes from the host using
the I/O Operations component of System Automation for OS/390 (SA/390). The use of I/O
Operations reduces the requirement for physical access to the ESCON Director console, but
it does not remove the requirement for the console to be available. The console is required if
matrix configuration changes are to be saved to the HDD in the console PC.
q For maximum availability, a backup console should be maintained if the Directors provide
access to critical system or application data. There are two options for configuring the
backup console:
Maintain a PC with all current configuration files but without attachment to the LAN.
This PC may have the same IP address as the primary Director Console. In the event
of a failure of the primary console, its LAN connection can be transferred to the
secondary console. This is referred to as a replacement console.
Maintain a PC with all current configuration files and LAN attachment. An additional
unique IP address will be required for this PC. The ESCON Director Console
Application on the backup PC must not be active. In the event of a failure of the primary
console, the ESCON Director Console Application can be started on the secondary
console. This is referred to as a backup console.
q For normal operations and management, we recommend the use of I/O Operations rather
than the Director console.
2.6.2 FICON Switches
At the time of writing, IBM markets multiple FICON switches: The Inrange FC9000, the
McDATA Intrepid, and the IBM 2109 Model 12.
The FC/9000 and Intrepid features N+1 redundancy for all of its elements. This redundancy
results in high availability. Even in the case of failure of any internal elements, the FICON
Switch remains operational. All activities, including code loads, code-activation, and
replacement of failed parts can be done nondisruptively.
q In the event of a failure you shall always configure at least two FICON switches and
spread the channels between the two directors.
q Before installing the FICON switch, consider where to connect your FICON channels from
the server and the control unit ports, as well as the ISLs (if applicable), based on your
requirements.
Distribute the channels among different cards.

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