HP-UX SNAplus2 R7 Administration Guide
Configuring APPC Communication
Defining TPs
Multiple instances supported
If you do not select this option, the TP is a queued TP. Any incoming Allocate requests arriving while the
TP is running are queued until the TP issues another Receive_Allocate, or until it finishes running and can be
restarted. An incoming Allocate request is routed to this TP only if it is received by an LU that is con
figured
to route incoming Allocate requests to this computer, or if it is received by an LU on this computer that has
no routing information configured.
If you select this option, the TP is a nonqueued TP. SNAplus2 starts a new copy of the TP each time an
incoming Allocate request arrives for it. A nonqueued TP cannot be started by an operator; it is always
started automatically by SNAplus2. For a nonqueued TP, SNAplus2 permits more than one copy of the TP
to be running at a time. All copies run with the same user and group IDs and the same working directory, as
defined by the
User ID and Group ID parameters. If the TP writes to files on the local system, you need to
ensure that different copies of the TP do not overwrite each other’s files.
After a nonqueued TP has ended a conversation, it may terminate, or it may issue another RE-
CEIVE_ALLOCATE. For frequently-used programs, this provides a way of avoiding the performance over-
head of starting a new instance of the program for each conversation. Each time an Attach is received for
a nonqueued, automatically started TP, SNAplus2 checks whether there is already a RECEIVE_ALLOCATE
outstanding from an instance of this TP. If so, this TP is used for the incoming conversation; otherwise,
SNAplus2 starts a new instance of the program.
Route incoming Allocates to running TP
This option applies only if multiple instances are not supported.
Select this option if the TP is a broadcast queued TP. Any incoming Allocate requests arriving while the TP
is running are queued until the TP issues another Receive_Allocate, or until it finishes running and can be
restarted. When the TP is started, information about the TP is broadcast to all servers on the LAN; if an LU
on another computer receives an incoming Allocate request and has no routing information configured, it can
dynamically locate the TP and route the Allocate request to it.
Using this option avoids having to configure explicit routing information on LUs, and enables load-balancing
by running more than one copy of the same TP on different computers. However, if you want to avoid
broadcasting information in order to reduce LAN traffic, or if you need to ensure that incoming Allocate
requests arriving at a particular LU are always routed to the same copy of the TP, do not select this option.
Full path to TP executable
The full path and file name of the executable file for this TP.
The file must have execute permission for the user specified by the User ID parameter. In addition, if the
executable file is to be run with User ID set to root, the file must be owned by root and must have
setuid
and setgid permission in order to be started automatically by SNAplus2.
Arguments
Any command-line arguments to be passed to the TP, separated by spaces. The arguments are passed to the
TP in the same order as they appear here.
This value is optional. If it is not included, the TP is invoked without any command-line arguments.
User ID
The user ID that SNAplus2 uses to start the TP. This line is required, and must be specified. The ID must be
a valid HP-UX login ID on the SNAplus2 computer.
The TP is started in the home directory associated with this user ID. This home directory is also the default
path for trace files and any other files accessed by the TP (unless the application overrides it by specifying a
full path). If the application specifies a file name without a path, SNAplus2 searches for the file in this home
directory; if the application specifies a file name with a relative path, SNAplus2 searches for the file in the
specified directory relative to this home directory.
The executable file for the TP, specified by the Full path to TP executable parameter, must have execute
permission for the specified user. In addition, if User ID is set to root, the file must be owned by root and
must have setuid and setgid permission in order to be started automatically by SNAplus2.
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