Escon channel port enablement feature

6947ch03.fm

Draft Document for Review April 7, 2004 6:15 pm

ESCON channel port enablement feature

The 15 active ports on each 16-port ESCON feature are activated in groups of 4 ports via Licensed Internal Code - Control Code (LIC-CC), by using the ESCON channel port feature (feature code 2324).

The first group of 4 ESCON ports requires two 16-port ESCON features. After the first pair of ESCON cards is fully allocated (by 7 ESCON ports groups, using 28 ports), single cards are used for additional ESCON ports groups.

Ports are activated equally across all installed 16-port ESCON features for high availability. In most cases, the number of physically installed channels is greater than the number of active channels that are LIC-CC enabled. This is not only because the last ESCON port (J15) of every 16-port ESCON channel card is a spare, but also because several physically installed channels are typically inactive (LIC-CC protected). These inactive channel ports are available to satisfy future channel adds.

If there is a requirement to increase the number of ESCON channel ports (minimum increment is four), and there are sufficient unused ports already available to fulfill this requirement, then IBM manufacturing provides an LIC-CC diskette to concurrently enable the number of additional ESCON ports ordered. This is illustrated in Figure 3-10 on page 94. In this case, no additional hardware is installed.

110

J00

120

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J00

120

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111

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J01

112

J01

J02

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J03

LICCC

PCHID

J04

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Number

J06

ENABLEMENT

J06

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J08

J09

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J11

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ESCON-16

SPARE

CHANNEL

Figure 3-10

16-port ESCON - LIC-CC

An ESCON channel add will never activate the spare channel port. However, if the spare port on a card was previously used, then the add may activate all the remaining ports on that card.

If there are not enough inactive ports on existing 16-port ESCON cards installed to satisfy the additional channel order, then IBM manufacturing ships additional 16-port ESCON channel card(s) and an LIC-CC diskette.

If there has been multiple sparing on a 16-port ESCON card and, by replacing that card the additional channel add can be satisfied, the card will be replaced.

94IBM eServer zSeries 990 Technical Guide

990 specifications

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IBM 990 manual Escon channel port enablement feature

Models: 990

ESCON channel port enablement feature

990 specifications