In z/OS® V1R8,
the master console has been removed. The value of the master console
has decreased over time. Historically, the master console had been
used for important messages that required the highest level of authority
to take action.
Table 1 details the
functions that were unique to the master console that are now available
to other consoles.
Table 1. Functions
that were unique to the master console that are now available to other
consolesFunctions |
z/OS V1R7
and lower releases |
z/OS V1R8
and higher releases |
---|
Routing codes 1 and 2 |
The master console was forced to have routing
codes 1 and 2 assigned to it and they could not be removed. |
Routing codes 1 and 2 are no longer forced to
any console. Make sure routing codes 1 and 2 are assigned to the appropriate
console definitions in CONSOLxx. |
Console id 0 ( internal console ID (X’00000000’)) |
All messages targeted for console id 0 were
delivered to the master console. |
All messages targeted for console id 0 will
go to any console that has the INTIDS routing attribute. INTIDS may
be specified in CONSOLxx or through the VARY CN command. |
Table 2 details the
functions that affected the master console that have been changed.
Table 2. Functions
that affected the master console that have been changedFunctions |
z/OS V1R7
and lower releases |
z/OS V1R8
and higher releases |
---|
External interrupt key |
The external interrupt key was used to switch
the master console function to another console. |
Since there is no longer a master console the
external interrupt key on the hardware management console is not supported. |
SYNCHDEST |
The master console (*MSTCON*) could be specified
in the SYNCHDEST group as a destination for synchronous messages. |
The master console (*MSTCON*) is ignored. You
need to explicitly specify by name any consoles you expect to receive
synchronous messages. The system console remains the synchronous message
destination of last resort. |
Synchronous message destination default (no
SYNCHDEST group defined) |
The master console was used if available on
the system where the message was issued, otherwise the system console
on that system was used. |
The system console on the system where the message
was issued is used. |
Table 3 details the
remaining functions that were affiliated with the master console and
removed.
Table 3. Remaining
functions that were affiliated with the master console and removedFunctions |
z/OS V1R7
and lower releases |
z/OS V1R8
and higher releases |
---|
Console switch and the SWITCH CN command |
Console switch and/or the SWITCH CN command
was used to switch a failing console to an alternate console. |
The main purpose was to ensure the availability
of the master console. Since the master console has been removed the
need for console switch and SWITCH CN command has also been removed.
This reduces the complexity of console definitions and the difficulties
of finding the location of the master console after a console switch. |
Hardcopy switch |
Depending on your configuration of OPERLOG
and SYSLOG, when one failed, hardcopy could automatically switch to
the other. |
There is no switching between hardcopy mediums,
therefore to maintain the same level of functionality, run with both
SYSLOG and OPERLOG as your hardcopy medium. |
ALTGRP (alternate group) |
The ALTGRP function was used in selecting an
alternate console. |
There is no longer a need for the ALTGRP (alternate
group) function because of the elimination of console switch. Note: The
Parmlib(CNGRPxx) member is still used for AUTOACT and SYNCHDEST. In
V1R8 and higher the ALTGRP(x) keywords need to be removed from the
CONSOLxx parmlib member.
|
NOCC and NOMCC |
NOCC (no consoles condition) and NOMCC (no master
console condition) were considered to be undesirable conditions. NOCCGRP
specification in CONSOLxx specifies the name of the console group
defined in CNGRPxx from whose members the system or sysplex can select
a master console during a no consoles condition. |
NOCC and NOMCC are no longer considered undesirable
conditions and can be considered an acceptable running console environment.
The specification of NOCCGRP is ignored. |
Table 4 details the
functions changed to help run your sysplex.
Table 4. Changed
function to help you run your sysplex.Functions |
z/OS V1R7
and lower releases |
z/OS V1R8
and higher releases |
---|
SYSCONS (system console or hardware
management console) |
SYSCONS authority was installation defined. |
SYSCONS always has master authority
to insure there is always a master authority console available. |
In V1R7 the external use of 1 byte console IDs was
removed. If you compiled a program that used 1 byte console
IDs, compilation would fail. But existing compiled programs that
used 1 byte console IDs would continue to execute as before.
In z/OS V1R8
and higher releases, 1-byte console IDs (and EMCS migration ids) are
eliminated. All messages targeted for 1 byte console IDs will go to
any console that has the UNKNIDS routing attribute. UNKNIDS may be
specified in CONSOLxx or through the VARY CN command.