Subsystem Control Point (SCP) Management Programming Manual

SPI Programming Considerations for SCP
Subsystem Control Point (SCP) Management Programming Manual—520619-001
3-7
D-Series Changes
D-Series Changes
These changes directly affect programmatic management of SCP processes:
•
SCP processes are based on the ZCMK definitions, and therefore include ZCMK-
defined tokens in commands and response messages and allow additional process
startup parameters.
•
Management applications can use the new subsystem manager process identification
token ZCOM-TKN-XMGR to identify the SCP process to which a command is
directed. See Command-Message Routing on page 3-3.
•
SCP processes forward new requester identification (REQID) tokens to converted
subsystems. See Requester Identification on page 3-5.
•
SCP processes use new token and token data type definitions to convey D-series
data structures. See Section 4, Common Definitions.
•
SCP processes support the ALTER, RESETSTATS, and STATISTICS commands
in addition to those commands supported by C-series SCP processes. See Section 5,
Commands and Responses.
•
SCP processes can issue ZCOM, ZCMK, and additional ZSCP event messages. See
Section 6, Event Messages.
•
D-series subsystems omit C-series tokens and fields from responses if those tokens
cannot accommodate D-series data. See Obsolete Fields in Structured Tokens
on
page 3-8.
•
Communications among SCP processes and other processes is restricted. See
Interprocess Communications Restrictions on page 3-9.
•
The tracing information structure ZCOM-DDL-TRACE-MODIF has been retired
and replaced by ZTRC-DDL-TRACE-MODIF.
•
An SCP process does not initiate Communications Management Process (CMP)
traces.
Implications for Management Applications
In general, an application that ran on a C-series node runs without modification at a low
PIN on a newer node. In particular, management processes currently running on a C-
series node should run identically on a D-series node or on a C-series node in a network
with a D-series node so long as all the processes involved are running at low PINs. The
SCP and subsystem processes that communicate with an unconverted management
application should be run at low PINs. This is the best way, other than converting the
application, to avoid the problems described in these subsections.
Obsolete Tokens in Responses
Even when an SCP process returns new tokens to convey data, it continues to include
the same information in previously used tokens if the data fits in the old tokens. If the
returned values do not exceed the range supported by the old tokens, an unconverted
requester sees no change. (The requester can ignore the additional new tokens included
in the response.)