This section describes how to start a Natural RPC server on the different platforms.
The following topics are covered:
Starting a Natural RPC Server in a Mainframe Online Environment (all TP Monitors)
Starting a Natural RPC Server in a Mainframe Online Environment (CICS only)
Starting a Natural RPC Server in a Mainframe Online Environment (Com-plete only)
Considerations for Mainframe Natural RPC Servers with Replicas
Starting a Natural RPC Server Using the RPC Server Front-End (z/OS Batch Mode only)
Starting a Natural RPC Server Using the RPC Server Front-End (CICS only)
Any kind of Natural session can be used as a Natural RPC server, but typically a Natural server is a Natural session which is started as an asynchronous task or as a background task.
For the purpose of starting a server, you have the following options:
Create an RPC server-specific Natural parameter module.
For a list of the relevant parameters, refer to the section Setting Up a Natural RPC Environment, Set the RPC Server-Specific Natural Parameters.
This parameter module is linked to your Natural.
Alternatively, you can also specify the RPC server-specific Natural profile parameters dynamically.
The RPC server-specific Natural profile parameters may also be
specified in a Natural profile created with the
SYSPARM
utility. Natural would then be started with
PROFILE=serverprofile
where serverprofile is
the name of the Natural profile.
For the purpose of starting a server, you have the following options:
Create an RPC server-specific Natural parameter file.
For a list of the relevant parameters, refer to the section
Setting Up a Natural RPC
Environment,
Set the RPC
Server-Specific Natural Parameters. As it is strongly
recommended to start a Natural RPC server with the Natural profile parameter
BATCHMODE, you should
additionally specify the Natural profile parameters
CMSYNIN,
CMOBJIN and
CMPRINT.
Natural will then be started with
PARM=serverparm
where serverparm is the
name of the parameter file.
Alternatively, you can specify the RPC server-specific Natural profile parameters dynamically.
How a Natural server is started depends on the environment and is described in the corresponding paragraphs below. For the sake of simplicity, only the mandatory RPC server-specific profile parameters are shown. The optional RPC server-specific profile parameters may be specified analogously.
To start a Natural server in a mainframe online environment
In your TP monitor environment, enter the following command:
<natural> PROFILE=serverprofile
Or:
<natural> RPC=(SERVER=ON,SRVNAME=servername,SRVNODE=nodename,RPCSIZE=n,MAXBUFF=n)
Where <natural> is the
name with which you start your Natural (transaction code, transaction ID,
environment-dependent nucleus name) and
serverprofile is the name of the
Natural profile.
In a CICS environment, you will typically start a Natural RPC server in asynchronous mode. In addition to the options described above for all TP monitors, you have the following options for this purpose:
You can use the Natural program STARTSRV in library
SYSRPC to start a Natural server in asynchronous mode (see
below).
You can start a Natural RPC server in asynchronous mode during startup of CICS (see below).
When starting the asynchronous Natural RPC server, it is
recommended to specify the Natural profile parameters
TTYPE,
INTENS,
SENDER in addition, using the
following settings:
TTYPE=ASYL,INTENS=1,SENDER=CSSL
This will cause each output to the primary output destination to be
written in line mode rather than in 3270 mode. Instead of CSSL,
you may specify any other CICS output destination.
STARTSRV is a sample front-end for RPCSSRV
that starts the asynchronous Natural session.
By default, the asynchronous Natural is started with the same transaction ID in the same library as the current session.
If Natural Security (NSC) is used, the user ID of the current Natural session is propagated, too. You may adapt the input to your requirements.
Note that some Natural profile parameters are implicitly added by
RPCSSRV. This applies especially to the keyword subparameter
RPCSIZE
of profile parameter RPC. RPCSIZE
defaults to MAXBUFF+4, where MAXBUFF is the value
entered in the map field Receiving buffer. You may
overwrite the default value for RPCSIZE by entering
RPC=(RPCSIZE=n) in the map field
Session parameter.
If you want to execute a Natural program during startup of the
Natural session, you may use the map field User Stack. The
content of User Stack is put on the Natural
STACK and executed before the Natural server is activated.
To show the Natural profile parameters involved, enter
*SHOW* in the Transaction ID field.
STARTSRV will show you all dynamic profile parameters that will be
used by RPCSSRV to start the asynchronous Natural session.
To start a Natural RPC server session in asynchronous mode during startup of CICS, proceed as follows:
Use the PLTPI to start a program that uses EXEC
CICS START to start a Natural session with all required RPC specific
Natural profile parameters. You may adapt the sample PLTPI program
XNCIFRNP that is provided in the Natural CICS source library.
Please note that the Natural session is started under the CICS
default user ID, which, by default, is CICSUSER. This user ID is
assigned to the Natural system variables
*INIT-USER
and *USER. If
your Natural session is running under Natural Security, you may therefore have
to put a Natural LOGON command on the Natural
STACK.
In a Com-plete environment, you will typically start a Natural RPC server in asynchronous mode. In addition to the options described above for all TP monitors, you have the following options for this purpose:
You can use the Natural program STARTSRV in library
SYSRPC to start a Natural server in asynchronous mode (see
below).
You can start a Natural RPC server in asynchronous mode during startup of Com-plete (see below).
STARTSRV is a sample front-end for RPCSSRV
that starts the asynchronous Natural session.
By default, the asynchronous Natural is started with the same Natural name in the same library as the current session.
If Natural Security (NSC) is used, the user ID of the current Natural session is propagated, too. You may adapt the input to your requirements.
Note that some Natural profile parameters are implicitly added by
RPCSSRV. This applies especially to the keyword subparameter
RPCSIZE
of profile parameter RPC. RPCSIZE
defaults to MAXBUFF+4, where MAXBUFF is the value
entered in the map field Receiving buffer. You may
overwrite the default value for RPCSIZE by entering
RPC=(RPCSIZE=n) in the map field
Session parameter.
If you want to execute a Natural program during startup of the
Natural session, you may use the map field User Stack. The
content of User Stack is put on the Natural
STACK and executed before the Natural server is activated.
To show the Natural profile parameters involved, enter
*SHOW* in the Transaction ID field.
STARTSRV will show you all dynamic profile parameters that will be
used by RPCSSRV to start the asynchronous Natural session.
To start a Natural RPC server session in asynchronous mode during startup of Com-plete, proceed as follows:
Use the startup option (sysparms) STARTUPPGM to start a
Natural session with all required RPC-specific Natural profile parameters. You
may either specify the required RPC-specific parameters individually or use a
Natural profile to specify them as follows:
STARTUPPGM='<natural> PROFILE=<serverprofile>'
Please note that the Natural session is started under the user ID
under which Com-plete is started. This user ID is assigned to the Natural
system variables *INIT-USER
and *USER. If
your Natural session is running under Natural Security, you may therefore have
to put a Natural LOGON command on the Natural
STACK.
A batch server is a standard Natural batch session that is started with the RPC parameters described in the section Setting Up a Natural RPC Environment, Set the RPC Server-Specific Natural Parameters.
The following topics are covered below:
Note:
For a sample JCL using the trace facility, refer to
Operating a Natural RPC
Environment,
Using the
Server Trace Facility.
//NATRPC JOB CLASS=K,MSGCLASS=X // EXEC PGM=NATOS,REGION=8M <== Note 1 //STEPLIB DD DISP=SHR,DSN=SAG.NAT.LOAD // DD DISP=SHR,DSN=SAG.EXX.LOAD // DD DISP=SHR,DSN=SAG.ADA.LOAD <== Note 2 // DD DISP=SHR,DSN=DB2_load_library <== Note 3 //CMPRMIN DD * IM=D,MADIO=0,MT=0,OBJIN=R,AUTO=OFF,MAXCL=0,ID=',',INTENS=1, RPC=(SERVER=ON,SRVNAME=servername,SRVNODE=nodename) RPC=(RPCSIZE=m,MAXBUFF=n), STACK=(LOGON serverlibrary,userID,password) /* //CEEOPTS DD * <== Note 4 POSIX(ON) /* //SYSUDUMP DD SYSOUT=X //CMPRINT DD SYSOUT=X /*
Notes:
EXEC
PARM statement will pass Natural parameters only to the main task.
Instead, use the
CMPRMIN statement to pass parameters
to the main task and the subtasks simultaneously.
ADAUSER
or the Natural profile parameter ADANAME is used.
A sample JCL for a started task is provided in the Natural for mainframes installation documentation; see Installing Natural on z/OS.
You can also run a batch server with replicas by setting the
keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC to a value greater than 1.
Replicas are attached to a Natural main task as additional server tasks. They enable you to start several identical servers in the same region.
To start a Natural RPC server under Windows
Create a shortcut for Natural.
Enter the shortcut properties.
In the Target text box, edit the Natural path and append:
"<Path>\natural.exe" batchmode parm=serverparm
where serverparm is the name of the parameter
file.
Or:
"<Path>\natural.exe" batchmode server=on srvname=servername srvnode=nodename maxbuff=n cmsynin=cmsynin cmobjin=cmobjin cmprint=cmprint
To start a Natural RPC server under Linux
Enter the following command:
natural batchmode parm=serverparm &
where serverparm is
the name of the parameter file.
Or:
natural batchmode server=on srvname=servername srvnode=nodename maxbuff=n cmsynin=cmsynin cmobjin=cmobjin cmprint=cmprint &
The main task and all replicas run in the same z/OS region.
Use the reentrant batch link routine ADALNKR
instead of ADALNK.
If you want to use ADAUSER, you must not link
ADAUSER with your front-end, because ADAUSER is
non-reentrant (see Item 5). Instead, use the Natural profile parameter
ADANAME and set
ADANAME=ADAUSER. This will cause Natural to load
ADAUSER dynamically at runtime.
In the Natural parameter module:
Set the keyword subparameter
NTASKS=n
of profile parameter RPC or parameter macro
NTRPC, where
n is the number of parallel servers
(< 100) to be started, including the main task.
Use the Natural profile parameter
ETID to
specify the Adabas user identification as a blank character. This is necessary
to prevent a NAT3048 error (ETID not unique in Adabas nucleus) when the subtask
is started.
When using dynamic Natural profile parameters:
Use the dynamic parameter dataset CMPRMIN to
pass the dynamic Natural profile parameters to Natural. Do not use the
PARM card or the primary command input dataset
CMSYNIN.
When using a local buffer pool (z/OS only):
Each subtask allocates its own local buffer pool unless you
specify a shared local buffer pool. See subparameter
LBPNAME of
profile parameter OSP or parameter macro
NTOSP (in the Parameter
Reference documentation).
In the Natural front-end link job (z/OS only):
Link the front-end reentrant by using the RENT
option of the linkage editor.
If the front-end were not linked with the RENT
option, only the main task would start the communication with the EntireX
Broker. All subtasks would be set to a WAIT status by z/OS, until
the main task would have been terminated. If you would terminate the RPC server
lateron, the address space would hang and would have to be cancelled.
Make sure that any other modules that are additionally linked to the Natural nucleus are reentrant. Any dynamically loaded programs must also be reentrant.
Note for z/OS: If you cannot
make a module reentrant, link the module as non-reusable; this means, you
should not specify the link option RENT or
REUS. This is to ensure that each subtask will get its own
copy.
For a sample JCL, see Using the Server Trace Facility.
In z/OS batch mode, a Natural RPC server may alternatively be started using the RPC server front-end. This approach is required with impersonation and is optional in other cases.
If you use the RPC server front-end without impersonation, you are
recommended to set the keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC to a value greater than 1.
Otherwise, there will be no benefit. The
Considerations
for Mainframe Natural RPC Servers with Replicas apply also
when you are using the RPC server front-end.
The RPC server front-end uses the Natural Server functionality; see Natural as a Server under z/OS (in the Natural Operations documentation). It is characterized by the following features:
The Natural RPC server front-end starts a number of Natural RPC
server sessions as specified by the keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC.
All Natural RPC server sessions run with the same Natural profile parameter settings.
The Natural profile parameter settings are taken from the Natural parameter module and may be overwritten by dynamically specified profile parameters that are passed with the transaction ID. The dynamically specified profile parameters must follow the startup parameter.
If all Natural RPC server sessions are currently in use by
clients (executing a client request or waiting for the next request within a
conversation) and if the keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC is set to a value greater than
one, auxiliary Natural RPC server sessions are started. These Natural RPC
server sessions are automatically terminated on the first EntireX Broker
timeout, provided that there is at least one other Natural RPC server session
not in use by a client. If all other Natural RPC server sessions are being used
by clients, the auxiliary RPC server session will stay up until the next
EntireX Broker timeout. This makes sure that there is always a Natural RPC
server available to process a new client request.
The Natural RPC server sessions are executed in a thread environment that is similar to Natural sessions executing in a TP monitor system.
With impersonation:
At the end of a non-conversational CALLNAT and at
the end of a conversation, all database sessions and all work files are closed.
This ensures that the next client request will open the database and the work
files with its own user ID.
Without impersonation:
After the first EntireX Broker timeout, all database sessions and
all work files are closed. This ensures that no resources are blocked during
wait times.
The required startup parameters are passed in the
PARM= parameter of the EXEC statement in
the JCL. These parameters are:
The name of the Natural z/OS batch nucleus;
The size of a storage thread;
The optional keyword UCTRAN.
UCTRAN indicates that all messages of the RPC
Server front-end are converted into upper case.
These parameters must be separated by commas and must be entered without leading or trailing blanks:
| PARM='Natural-z/OS-batch-nucleus,size-of-thread[,,UCTRAN]' |
Note:
For compatibility reasons UCTRAN must be preceded
by two consecutive commas.
See also the Sample JCL below.
The Natural z/OS batch nucleus is dynamically loaded.
The load library containing the z/OS batch nucleus must be available in the steplib concatenation.
The EntireX Broker stub NATETB23 must not be
used.
The EntireX Broker is accessed outside the Natural context.
Therefore, you must use the EntireX Broker stub BROKER, see
Providing Access
to the EntireX Broker Stub on Mainframe.
With impersonation only:
When the impersonation feature
is used, the Natural RPC server calls Natural Autorized Services Manager
(NATASMvv) to do the impersonation. No APF authorization is required for the
Natural RPC server itself.
With Natural Security only:
If the Natural RPC server front-end is started with profile parameter
AUTO=OFF, you must
provide a Natural LOGON command
with library ID, user ID and password on the Natural stack: STACK=(LOGON
library-id;user-id;password).
//NATRPC JOB CLASS=K,MSGCLASS=X // EXEC PGM=RPC-FRONT,REGION=8M <== Note 1 // PARM='Natural-z/OS-interface-module,1000' //STEPLIB DD DISP=SHR,DSN=SAG.NAT.LOAD // DD DISP=SHR,DSN=SAG.EXX.LOAD // DD DISP=SHR,DSN=SAG.ADA.LOAD <== Note 2 // DD DISP=SHR,DSN=DB2_load_library <== Note 3 //CMPRMIN DD * IM=D,MADIO=0,MT=0,OBJIN=R,AUTO=OFF,MAXCL=0,ID=',',INTENS=1, PRINT=((10),AM=STD) RPC=(SERVER=ON,SRVNAME=servername,SRVNODE=nodename,NTASKS=3) RPC=(RPCSIZE=m,MAXBUFF=n,TRACE=2), RCA=BROKER,RCALIAS=(BROKER,BROKER) STACK=(LOGON serverlibrary,userID,password) /* //CEEOPTS DD * <== Note 4 POSIX(ON) * //SYSUDUMP DD SYSOUT=X //CMPRT10 DD SYSOUT=X //CMPRT101 DD SYSOUT=X //CMPRT102 DD SYSOUT=X //CMPRT199 DD SYSOUT=X //CMPRINT DD SYSOUT=X //CMPRINT1 DD SYSOUT=X //CMPRINT2 DD SYSOUT=X //CMPRIN99 DD SYSOUT=X /*
If the RPC server is running with subtasks, the EXEC PARM statement will pass Natural parameters only to the main task. Instead, use the CMPRMIN statement to pass parameters to the main task and the subtasks simultaneously.
Applies only if the Adabas link routine ADAUSER or the Natural profile
parameter ADANAME is used.
Applies to DB2 users only.
Applies only if SSL is used.
In CICS, a Natural RPC server may alternatively be started using the RPC server front-end. This approach is required when impersonation is used and is optional in other cases.
If you use the RPC server front-end without impersonation, you are
recommended to set the keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC to a value greater than 1.
Otherwise, there will be no benefit.
The RPC server front-end uses the Natural Server functionality. It is characterized by the following features:
The Natural RPC server front-end is started via the transaction ID defined in the Customize CICS step for the Natural RPC server front-end;
see Installing the Natural CICS Interface on z/OS.
The transaction ID may either be entered at a terminal or you
may use the Natural program STARTSFE in library
SYSRPC to start the Natural RPC server front-end in asynchronous
mode.
The Natural RPC server front-end requires the name of the Natural CICS Interface nucleus as startup parameter. This startup parameter is passed with the transaction ID.
The Natural RPC server front-end starts a number of Natural RPC
server sessions as specified by the keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC.
All Natural RPC server sessions run with the same Natural profile parameter settings.
The Natural profile parameter settings are taken from the Natural parameter module and may be overwritten by dynamically specified profile parameters that are passed with the transaction ID. The dynamically specified profile parameters must follow the startup parameter.
If all Natural RPC server sessions are currently in use by
clients (executing a client request or waiting for the next request within a
conversation) and if the keyword subparameter
NTASKS
of profile parameter RPC or parameter macro
NTRPC is set to a value greater than
one, auxiliary Natural RPC server sessions are started. These Natural RPC
server sessions are automatically terminated on the first EntireX Broker
timeout, provided that there is at least one other Natural RPC server session
not in use by a client. If all other Natural RPC server sessions are being used
by clients, the auxiliary RPC server session will stay up until the next
EntireX Broker timeout. This will ensure that there is always a Natural RPC
server available to process a new client request.
The Natural RPC server sessions are executed in a thread environment that is similar to Natural sessions executing in a TP monitor system.
All inactive Natural RPC server sessions (sessions that wait for a client request) are rolled out using the Natural Roll Facilities under CICS which are defined for the Natural CICS Interface nucleus in use.
At the start of a non-conversational CALLNAT and at
the start of a conversation, a new CICS worker task is started under the user
ID of the client by using the USERID() option of the EXEC
CICS START TRANSID() command. The client request is executed by Natural
in this worker task. While the client request is executed, the Natural RPC
server session waits for the worker task to finish.
At the end of a non-conversational CALLNAT and at
the end of a conversation, the worker task is terminated and all databases are
closed and all CICS resources are freed. This ensures that the next client
request will open the database and access the CICS resources with its own user
ID.
The client request is executed by the Natural RPC server session itself.
After the first EntireX Broker timeout, all databases are closed and all CICS resources are freed. This will ensure that no resources are blocked during wait times.
The required startup parameters are passed with the transaction ID. These parameters are:
The name of the Natural CICS Interface nucleus <ncistart>.
The optional keyword UCTRAN.
UCTRAN indicates that all messages of the RPC
Server front-end are converted into upper case.
An optional Natural profile parameter string.
<natural> <ncistart>[,UCTRAN] RPC=(SERVER=ON,SRVNAME=servername,SRVNODE=nodename,RPCSIZE=n, MAXBUFF=n) RCA=BROKER,RCALIAS=(BROKER,CICSETB)
Where <natural> is the transaction ID with
which you start your Natural RPC server front-end and
<ncistart> is the name of your Natural CICS Interface
nucleus.
If the Natural
Roll Server is required (NCMDIR
parameter ROLLSRV is
set to YES), you must start a Natural Roll Server for the used
subsystem-id (as defined by Natural profile parameter
SUBSID) before the
Natural RPC server front-end is started.
The transaction ID of the RPC server front-end is used to identify the RPC server environment.
Do not to start more than one Natural RPC server front-end with the same transaction ID.
The executable NCI module is dynamically loaded.
The load library containing the executable NCI module must be
available in the DFHRPL concatenation.
The EntireX Broker stub NATETB23 must not be
used.
The EntireX Broker is accessed outside the Natural context.
Therefore, you must use the EntireX Broker stub CICSETB, see
Providing Access to the EntireX Broker Stub on
Mainframe.
With impersonation only:
When the impersonation feature is used, the RPC server front-end
starts worker tasks. Ensure that the setting of the CICS system initialization
parameter MXT of your CICS installation is high
enough.
With Natural Security only:
If the Natural RPC server front-end is started with profile parameter
AUTO=OFF,
you must provide a Natural LOGON command with
library ID, user ID and password on the Natural stack: STACK=(LOGON
library-id;user-id;password).