This chapter describes the new TCP/IP enhancements.
This section contains the following topics:
In r17, CA IDMS provides the ability for DC/UCF systems and applications that execute within those systems to use logical service names in place of port numbers. The use of logical names allows port numbers to be changed without impacting application code or system definitions.
Port number independence is provided through the following facilities:
The new socket functions are described in GETSERVBYNAME and GETSERVBYPORT. The remainder of the new facilities are described below.
The CA IDMS services resolver is a new component of r17 responsible for translating service names to and from port numbers. It does this using the contents of a services file that can be included in the execution JCL of a DC/UCF system. The DDNAME or filename of the services file is specified in the new TCP/IP SYSGEN entity.
The services file contains a list of service names together with the port number, protocol and optional alias names associated with each one. This information is used when servicing a GETSERVBYNAME or GETSERVBYPORT socket function to retrieve the port number associated with a service name or the service name associated with a port number.
On z/OS, the default services data set is cataloged as <tcpip-hlq>.ETC.SERVICES. You can use this data set, a customized data set containing the definitions of the services that you want to use, or a combination of the two by concatenating the two files together. To ensure that the customized entries take precedence, include the customized data set before the system default data set.
During the initialization of the TCP/IP environment in a CA IDMS system, the services file is read and its contents converted to an internal structure that is stored in memory for efficient access. The contents of the in-core structure can be refreshed from the services file using the new DCMT VARY TCP/IP command.
Note: To allow updating the services file while it is in use by a CV, make it a member of a partitioned data set rather than a sequential file.
Each record within a services file defines a service name entry in character format.
Syntax
The syntax of the services data set records accepted by the CA IDMS services resolver follows the general standards for such files. The format is as follows:
►─ name ─ port#/protocol ─┬────────────┬─┬─────────────┬─────────────────────►◄ │ ┌─────────┐│ └─ # comment ─┘ └─▼─ alias ─┴┘
Parameters
Identifies the official Internet service name.
Identifies the port number. Port number is a positive number between 1 and 65535.
Identifies the protocol used for the service.
Identifies an unofficial name for the service.
Specifies comment text that continues until the end of the record.
Notes
The following illustrates a standard TCPIP.ETC.SERVICES data set delivered with the operating system:
# # Network services, Internet style # echo 7/tcp echo 7/udp discard 9/tcp sink null discard 9/udp sink null systat 11/tcp users daytime 13/tcp daytime 13/udp netstat 15/tcp qotd 17/tcp quote chargen 19/tcp ttytst source chargen 19/udp ttytst source ftp 21/tcp . . . . . . . . . . . .
More Information
To allow DC/UCF system definitions to be independent of port numbers, you can now specify a service name in place of a port number on LISTENER and DDSTCPIP PTERM SYSGEN statements and alter a service name using a DCMT VARY PTERM statement. Additionally the DCMT DISPLAY PTERM statement has been enhanced to report on the service name associated with a PTERM.
The PORT (for a LISTENER PTERM) and TARGET PORT (for a DDSTCPIP PTERM) parameters can now accept a service name in place of a port number value. The service name must be the name of a service in the services file with an associated protocol of TCP. Its length is limited to 32 characters.
When the corresponding PTERM is varied online, the CA IDMS services resolver tries to retrieve the port number associated with the service name. Regardless of the TCP/IP CASE option in effect for the system, CA IDMS always attempts to find the matching entry using the CASE SENSITIVE option first and if not found will then search using the CASE INSENSITIVE option. The same method is followed for the TCP protocol.
The output of a DCMT DISPLAY PTERM command displays the service name associated with a LISTENER or DDSTCPIP PTERM as illustrated in the following example.
Example
DCMT DISPLAY PTERM SY71CA31
Logical Term ID SY71CA31 Physical Term ID SY71CA31 Physical Line ID TCPIP Physical Term Type DDS TCP/IP Physical Term Model Physical Term Status InSrv Logical Term Status InSrv IP stack name *none (*DEFAULT) Target node SYSTEM71 Target host USILCA31 Target port 3771/DDS-TO-SYSTEM71 Port range OFF Idle interval 60 Permanent connections 3 Maximum connections OFF Active connections 1 Connections rejected 0 Number of Reads 0000000 Number of Writes 0000000 Number of Read Errors 0000000 Number of Write Errors 0000000
More Information
In a multiple TCP/IP stack environment, this feature lets you control or limit the stacks that are usable by the socket applications running in the CA IDMS system. This enhancement is primarily for CA IDMS systems running on z/OS with CINET active and on z/VM. It is useful in an environment where certain applications need to use secured sockets or some TCP/IP stacks are for testing only.
You can control or limit the TCP/IP stacks using the following methods:
The new SYSIDMS parameters are described below. For more information about the two other methods, see New TCP/IP System Entity.
Use the new SYSIDMS parameters to create an INCLUDE list or an EXCLUDE list of TCP/IP stack names to use at runtime. You can use these parameters to do the following:
Parameter Descriptions
(z/OS and z/VM only) Creates an EXCLUDE list of up to eight TCP/IP stack names to override the list of stacks supplied by the operating system or SYSGEN.
EXCLUDE_TCP/IP_STACK and INCLUDE_TCP/IP_STACK are mutually exclusive parameters and support wildcards.
(z/OS and z/VM only) Creates an INCLUDE list of up to eight TCP/IP stack names to override the list of stacks supplied by the operating system or SYSGEN.
EXCLUDE_TCP/IP_STACK and INCLUDE_TCP/IP_STACK are mutually exclusive parameters and support wildcards.
Examples
The following examples illustrate how to specify SYSIDMS parameters to create an INCLUDE list or an EXCLUDE list of TCP/IP stacks.
The SYSIDMS parameter that is processed first determines whether an INCLUDE list or an EXCLUDE list is built; any parameters from the other group are rejected.
The following group of parameters specifies a list of TCP/IP stacks to include in the INCLUDE list.
INCLUDE_TCP/IP_STACK=TCPIP31 INCLUDE_TCP/IP_STACK=TCPIP31A INCLUDE_TCP/IP_STACK=TCPIP31B
The following group of parameters specifies an EXCLUDE list of parameters to reject from the system list, the TCPIP31X stack and all the stacks starting with the RUNT pattern:
EXCLUDE_TCP/IP_STACK=TCPIP31X EXCLUDE_TCP/IP_STACK=RUNT*
More Information
For more information about SYSIDMS, see the CA IDMS Common Facilities Guide.
Support of TCP/IP in CA IDMS has been enhanced by enabling the TCP/IP runtime environment to be defined independently from a socket line. This consolidates the definition of the TCP/IP attributes that were previously specified in the SOCKET line definition and various SYSIDMS parameters and enables them to be displayed and varied using new DCMT DISPLAY TCP/IP and DCMT VARY TCP/IP commands.
The new TCP/IP entity provides the following benefits:
You define the TCP/IP runtime environment for a DC/UCF system through the new TCP/IP system generation statement or through the new DCMT VARY TCP/IP command. Both methods are described in the following sections. Enhancements to related SYSGEN and DCMT commands are also described.
The TCP/IP statement is used to define the TCP/IP runtime environment of a DC/UCF system.
Syntax
ADD/MODIFY/DELETE TCP/IP Statement
►►─┬─ ADD ─┬──┬─ TCP/ip ─┬──────────────────────────────────────────────► ├─ MODify ─┤ └─ TCPip ──┘ └─ DELete ─┘ ►──┬────────────────────────────────┬──────────────────────────────────────► └─ DEFault STATus is ─┬─ ON ◄──┬─┘ └─ OFF ──┘ ►──┬────────────────────────────────────────────┬──────────────────────────► └─ DEFault TCP_NODelay option is ─┬─ ON ───┬─┘ └─ OFF ◄─┘ ►──┬─────────────────────────────────────┬─────────────────────────────────► └─ DEFault STACk is ─┬─ DEFault ◄───┬─┘ └─ stack-name ─┘ ►──┬────────────────────────────────────────────────────────────────────┬──► │ ┌─────────────┐ ┌─────────────┐ │ └─┬─ INClude ─┬─ STAck (─▼─ stack-spec ┴) EXCept (─▼─ stack-spec ┴) ─┘ └─ EXClude ─┘ ►──┬─────────────────────────────────────────────────┬─────────────────────► └─ MAXimum NUMber of SOCkets is ─┬─ DEFault ◄───┬─┘ └─ max-socket ─┘ ►──┬───────────────────────────────────────────────────────────────────┬───► └─ MAXimum NUMber of SOCkets PER TASk is ─┬─ DEFault ◄────────────┬─┘ └─ max-socket-per-task ─┘ ►──┬────────────────────────────────────────┬──────────────────────────────► └─ PLUgin MODule is ─┬─ plugin-module ─┬─┘ └─ RHDCD1IP ◄─────┘ ►──┬─────────────────────────────────────────────────────────────────┬─────►◄ └─ SERvices FILe is ─┬─ OFF ◄───────────────────────────────────┬─┘ └─ file-name ─┬──────────────────────────┬─┘ └─ CASe ─┬─ SENsitive ◄──┬─┘ └─ INSensitive ─┘
DISPLAY/PUNCH TCP/IP Statement
►►─┬─ DISplay ─┬─┬─ TCP/ip ─┬─────────────────────────────────────────────────► └─ PUNch ───┘ └─ TCPip ──┘ ►─┬───────────────────────────────────────┬──────────────────────────────────► │ ┌───────────────────────────────────┐ │ │ │ ┌───────────────┐ │ │ └─▼─┬─ WITh ──────┬─▼─┬─ DETails ─┬─┴─┴─┘ ├─ ALSo WITh ─┤ ├─ HIStory ─┤ └─ WITHOut ───┘ ├─ ALL ─────┤ └─ NONe ────┘ ►─┬─────────────────────┬────────────────────────────────────────────────────► └─ AS ─┬─ COMments ─┬─┘ └─ SYNtax ───┘ ►─┬─────────────────────────────────┬────────────────────────────────────────►◄ └─ TO ─┬─ module-specification ─┬─┘ └─ SYSpch ───────────────┘
Parameters
These are equivalent keywords that can be used the same way everywhere. They can be specified in SYSGEN definitions or DCMT commands.
Specifies the status of TCP/IP support in CA IDMS. OFF disables TCP/IP support for CA IDMS at startup. ON enables support. The default is ON if an ADD TCP/IP statement is coded. If the TCP/IP entity is not defined to the system, the default is OFF.
Note: For compatibility with earlier releases, if the TCP/IP entity is not defined to SYSGEN, but the same system contains the definition of an enabled SOCKET line, TCP/IP is automatically enabled during startup. A warning message is displayed to the log recommending the use of the TCP/IP SYSGEN entity.
Note: The default TCP/IP status value defined to SYSGEN can be overwritten at startup by the new TCP/IP_STATUS=ON/OFF SYSIDMS parameter, and/or it can be changed dynamically at runtime using the new DCMT VARY TCP/IP command.
Specifies the default value for the TCP_NODELAY socket option. Unless overridden for a specific socket connection, this is the value that will be used for all communication. The default value is OFF, meaning that a delay may be experienced between consecutive sends in order to optimize overall data movement.
Note: On z/VSE, this option is ignored, as the TCP_NODELAYsocket option is not supported.
Specifies the default stack to be used by the DC/UCF system.
Identifies the name of the stack to be used as a default.
Specifies that the CA IDMS assigned default stack is to be used. DEFAULT is the default.
The default stack for a DC/UCF system varies by operating system.
Controls or limits the stacks that can be used by the socket applications running in the CA IDMS system. This option is useful only in a multiple stack environment where multiple TCP/IP stacks run concurrently; it is ignored on systems where only one TCP/IP stack is active. It is used differently depending on the operating system:
If specified, the resulting list of stacks depends on the type of list being defined:
Wildcards can be used as special names for stack-spec to define groups of stack names starting with the same pattern. When wildcards are used in the INCLUDE or EXCLUDE list, the EXCEPT list can be used to refine the set of included or excluded stacks by excluding specific stacks.
Wildcards can also be used for stack-spec in the EXCEPT list if they represent a sub-group of names from a larger group declared in the INCLUDE or EXCLUDE list. See examples at the end of this section.
This list can be used to replace the r16 definitions using the SYSTCPD file and the existing SYSIDMS parameters; these definitions are ignored when the stacks are defined through SYSGEN.
An empty list can be specified for the INCLUDE, EXCLUDE or EXCEPT list in order to remove all entries from the corresponding list. Duplicate names are ignored when specified within the same list of stacks.
Specifies the maximum number of sockets that can be created globally in the DC/UCF system. max-socket is a positive number between 1 and 65535. If DEFAULT is specified, a default value is assigned at startup. This default value depends on the operating system: 65535 on z/OS, 8000 on z/VSE, and 512 on z/VM.
The maximum number of sockets that can be created in one address space can also be limited by the operating system, for example, through USS definitions under z/OS.
Specifies the maximum number of sockets that can be created by a single task in the DC/UCF system. The maximum value and the default value for this parameter are both equal to the value assigned at runtime to max-socket. If the max-socket-per-task value is greater than max-socket, it is truncated.
Specifies the name of the plug-in module that implements support for specific TCP/IP stack implementations. The only plug-in module name that is accepted is RHDCD1IP; this is also the default value.
Defines the file to be used for translating service names to port numbers and vice versa.
Specifies the ddname (z/OS and z/VM) or the file name (z/VSE) of the services file.
If the data set or file corresponding to file-name cannot be found at runtime (DD card not specified in the startup JCL or data set not cataloged), an error message is written to the log file. Subsequent calls to the GETSERVBYNAME or GETSERVBYPORT socket function returns a specific ERRNO code.
Indicates that no services file is available and port number/service name resolution is not supported. OFF is the default.
Indicates whether the service name specified on input to a GETSERVBYNAME socket function is case-sensitive or case-insensitive. The default value is case-sensitive.
Example
Including or Excluding TCP/IP Stacks
This example illustrates a list of INCLUDE and EXCLUDE TCP/IP stack definitions and the TCP/IP stacks generated from them.
Assume the special system call on z/OS returns the following list of TCP/IP stacks as defined to CINET:
TCPSY100 - TCPSY110 - TCPSY200 - RUNTCP10 - RUNTCP11 - TESTTCP
The following SYSGEN definitions illustrate how to specify the TCP/IP stacks to include or exclude in the CA IDMS system:
MOD TCPIP INCLUDE STACK (TCPSY*,RUNTCP*) EXCEPT (TCPSY2*,RUNTCP11).
produces the following list of stacks:
TCPSY100 - TCPSY110 - RUNTCP10
MOD TCPIP INCLUDE STACK (*) EXCEPT (TCPSY*,TESTTCP).
produces the following list of stacks:
RUNTCP10 - RUNTCP11
MOD TCPIP EXCLUDE STACK (TCP*) EXCEPT (TCPSY200).
produces the following list of stacks:
TCPSY200 - RUNTCP10 - RUNTCP11 - TESTTCP
More Information
For more information about the system generation statements, see the CA IDMS System Generation Guide.
In prior releases, the name of the plug-in module was specified on the MODULE is plug-in clause of the SOCKET LINE SYSGEN statement. While this clause is still supported for upward compatibility, it is no longer required and the name of the plug-in module should now be specified using the PLUGIN MODULE clause of the new system generation TCP/IP statement.
Note: For more information about the PLUGIN MODULE clause, see
System Generation TCP/IP Statement.
The DCMT DISPLAY TCP/IP command displays information about the TCP/IP runtime environment of a DC/UCF system. In addition to current attribute settings, it can also display TCP/IP-related statistics and a list of all the TCP/IP stacks and their corresponding status.
Syntax
►►── DCMT ─┬───────────────────┬───────────────────────────────────────────► └─ broadcast-parms ─┘ ►── Display ─┬─ TCP/ip ─┬─────────────────────────────────────────────────► └─ TCPip ──┘ ►──┬─────────────────────┬───────────────────────────────────────────────┬►◄ ├─┬─── SUMmary ◄──────┤ │ │ ├─┬─ STATistics ──┬─┤ │ │ │ └─ STATS ───────┘ │ │ │ ├─┬─ STACk TABle ─┬─┤ │ │ │ └─ STACKS ──────┘ │ │ │ └─── ALL ───────────┘ │ │ │ ├─ SERvices FILe ─┬────────────────────────────┬──────────────────────┤ │ ├─ SORt ──┬─ BY ─┬─ NAMe ──┬─┘ │ │ └─ ORDer ─┘ └─ PORt ◄─┘ │ │ │ ├─ SERvices ─┬─ NAMe service-name ──────────────────────────────────┬─┤ │ └─ PORt port-number ─┬────────────────────────────────┬┘ │ │ └┬─ THRough ┬─ PORt port-number ─┘ │ │ └─ THRU ───┘ │ │ │ └─ SOCkets ─┬────────────────────┬──┬───────┬─────────────────────────┘ ├─ LTErm lterm-id ───┤ └─ ALL ─┘ └─ STAck stack-name ─┘
Parameters
Specifies to execute the DCMT command on all or a list of data sharing group members.
Note: For more information about broadcasting and broadcast-parms, see How to Broadcast System Tasks in the CA IDMS System Tasks and Operator Commands Guide.
Displays summary information about this system's TCP/IP environment. This is the default if no option is specified.
Displays statistics information.
Displays the TCP/IP stack table containing the name of all the stacks defined in the system. The output table contains five columns that provide the following information:
Displays all the information provided by the SUMMARY, STATISTICS, and STACK TABLE options.
Displays the contents of the services file, if one is in use. The output table contains three columns that provide the following information:
Aliases, if present, are displayed on secondary lines in the service name column.
The output table can be sorted by the service name or by the port number. By default, it is sorted by the port number.
Displays the contents of the services file, if one is in use but restricts the output to specific service names or specific port numbers.
Specifies the name of a specific service or a wildcard that displays all the services with a name starting with the same pattern.
When using the SERVICES PORT clause, you can specify a specific port number or a range of ports.
Specifies a port-number. port-number is a positive number between 1 and 65535. If the THROUGH PORT sub-clause is specified, the second port-number value must be greater than or equal to the first one.
Displays information about all LTERM's owning sockets in the system. The output table contains six columns (no ALL option) or ten columns (with ALL option) that display the following information:
Note: When the ALL option is specified and the current socket function is SELECT or SELECTX, the name of the function is displayed for the first socket descriptor only.
Examples
DCMT DISPLAY TCP/IP SUMMARY
SYSGEN definitions Run-time information ====================================== ====================================== Default status ON TCP/IP status Active Default TCP_NODELAY option OFF TCP_NODELAY option OFF Max number sockets 9999 Max number sockets 9999 Max number sockets per task 999 Max number sockets per task 999 Plugin module RHDCD1IP Services file SERVICES Services file case Sensitive Services file case Sensitive Default stack DEFAULT Default stack TCPIP31 Include stack list TCP* SYSIDMS parameters ====================================== EXCLUDE_TCP/IP_STACK TCPIP31V
DCMT DISPLAY TCP/IP STATISTICS
Statistics ===================================================== Number of sockets currently open 10 Number of sockets created 11 HWM of concurrent open sockets (global) 11 HWM of concurrent open sockets (1 LTERM) 1 Number of socket reads 98 Number of socket writes 64 Number of accepted connections rejected 0 Number of DDS connections rejected 0 Number of listener connections rejected 0
DCMT DISPLAY TCP/IP STACK TABLE
Hostname IP address Job name Active IPv6 ======== =============== =========== ====== ==== HOSTCA31 111.111.111.111 TCPIP31 (D) Y Y HOSTCA32 222.222.222.222 TCPIP32 Y Y TCPIP33 N RUNTCP Excl-G TCPIP31V Excl-I
DCMT DISPLAY TCP/IP SERVICES FILE
Services file SERVICES Services file case Sensitive Port# Protocol Service name or alias ===== ======== ===================== 7 tcp echo 7 udp echo 13 tcp daytime 13 udp daytime 15 tcp netstat 19 tcp chargen ttytst source 19 udp chargen ttytst source 21 tcp ftp 23 tcp telnet .. . . . . . .
DCMT DISPLAY TCP/IP SERVICE NAME nameserv*
Services file SERVICES Services file case Sensitive Port# Protocol Service name or alias ===== ======== ===================== 42 tcp nameserver 53 tcp nameserver 53 udp nameserver
DCMT DISPLAY TCP/IP SERVICE PORT 10 THROUGH 20
Services file SERVICES Services file case Sensitive Port# Protocol Service name or alias ===== ======== ===================== 13 tcp daytime 13 udp daytime 15 tcp netstat 19 tcp chargen ttytst source 19 udp chargen ttytst source
DCMT DISPLAY TCP/IP SOCKETS
Lterm-ID Pterm-ID Type Stack Socket-call Count ======== ======== ==== ======== =============== ===== LD000001 *No-PTE* FRST TCPIP31 1 SY71CA31 SY71CA31 DTCP TCPIP31 RECV (async) 2 TCLJSRV TCPJSRV LIST TCPIP31 ACCEPT (async) 1 TCPLIS01 TCPLIS01 LIST TCPIP31 ACCEPT (async) 1 VL72002 VP72002 3279 TCPIP31 ACCEPT 2
DCMT DISPLAY TCP/IP SOCKETS ALL
Lterm-ID Pterm-ID Type Stack Socket-call Socket-desc Dom NDL Timeout ======== ======== ==== ======== =============== =========== === === ======= LD000001 *No-PTE* FRST TCPIP31 0 IN N Forever SY71CA31 SY71CA31 DTCP TCPIP31 RECV 0 IN Y Forever TCPIP31 1 IN N Forever TCLJSRV TCPJSRV LIST TCPIP31 ACCEPT (async) 0 IN6 N Forever TCPLIS01 TCPLIS01 LIST TCPIP31 ACCEPT (async) 0 IN6 N Forever VL72002 VP72002 3279 TCPIP31 0 IN N 300 TCPIP31 ACCEPT 1 IN N 300
More Information
For more information about DCMT commands, see the CA IDMS System Tasks and Operator Commands Guide.
The DCMT DISPLAY LINE IPINFO option is no longer supported for a SOCKET LINE. The corresponding output can now be displayed using the DCMT DISPLAY TCP/IP ALL command.
Example
DCMT DISPLAY LINE TCPIP
*** Physical Line Display *** PLine-ID TCPIP Status InSrv Opened 2007-04-15-05.55.20.092194 Module IP LTerm-ID PTerm-ID Type/M Status Port Target-host SY71CA31 SY71CA31 DTCP OutSrv 00000 USILCA31 SY71CA11 SY71CA11 DTCP OutSrv 03771 USILCA11 TCPLIS01 TCPLIS01 LIST OutSrv 01234 TCLJSRV TCPJSRV LIST InSrv 03772 TCPIPB01 TCPIPB01 BULK Discon TCPIPB02 TCPIPB02 BULK Discon
Note: If a PTERM has a service name assigned to it, andthe PTERM status is out-of-service, the Port column shows the value 00000. You must issue an explicit DCMT DISPLAY PTERM command to display the corresponding service name.
More Information
The DCMT VARY TCP/IP command enables all the parameters that are defined in the system generation TCP/IP statement to be altered dynamically at runtime.
Syntax
►►── DCMT ─┬───────────────────┬────────────────────────────────────────────► └─ broadcast-parms ─┘ ►── Vary ─┬─ TCP/ip ─┬─────────────────────────────────────────────────────► └─ TCPip ──┘ ►─┬─ STAtus ─┬─ ON ─┬──────────┬───────────────────────────────────────┬┬─►◄ │ │ ├─ KEEp ◄──┤ ││ │ │ └─ RESet ──┘ ││ │ ├─ OFF ─┬─────────────────────────────────────────────────┬┤│ │ │ ├─ QUIesce ◄──┬──────────────────────┬┬─────────┬─┤││ │ │ │ └─ WAIt ─┬────────────┬┘├ KEEp ◄──┤ │││ │ │ │ ├ FORever ◄──┤ └ FORce ──┘ │││ │ │ │ └ wait-time ─┘ │││ │ │ └─ FORce ────────────────────────────────────────┘││ │ └─ CANcel ─┬─────────┬─────────────────────────────────────┘│ │ ├─ KEEp ──┤ │ │ └─ FORce ─┘ │ │ │ ├─ TCP_NODelay ─┬─ ON ──┬──────────────────────────────────────────────┤ │ └─ OFF ─┘ │ │ │ ├─ DEFault STAck stack-name ───────────────────────────────────────────┤ │ │ ├─┬─ INClude ─┬─ STAck stack-name ─────────────────────────────────────┤ │ └─ EXClude ─┘ │ │ │ ├─ MAXimum SOCkets max-socket ─────────────────────────────────────────┤ │ │ ├─ MAXimum SOCkets PER TASk max-socket-per-task ───────────────────────┤ │ │ ├─ SERvices FILe ─┬─ REFresh ────────────────┬─────────────────────────┤ │ └─ CASe ─┬─ SENsitive ───┬─┘ │ │ └─ INSensitive ─┘ │ │ │ └─┬─ STACk TABle ─┬─ REFresh ──────────────────────────────────────────┘ └─ STACKS ──────┘
Parameters
Specifies to execute the DCMT command on all or a list of data sharing group members.
Note: For more information about broadcasting and broadcast-parms, see How to Broadcast System Tasks in the CA IDMS System Tasks and Operator Commands Guide.
Switches the status of the TCP/IP support ON or OFF in the DC/UCF system.
Enables or reenables TCP/IP support in the DC/UCF system. If reenabling TCP/IP support in the system, the latest value of each option is kept.
Enables or reenables TCP/IP support in the DC/UCF system. If reenabling TCP/IP support in the system, the value of each option is set to its original value.
Prevents the creation of any new sockets, but allows executing applications using sockets to finish processing. All the LISTENER and DDSTCPIP PTERM's are closed. QUIesce is the default option for a DCMT VARY TCP/IP STATUS OFF command. By default, the QUIesce command waits indefinitely until all the socket descriptors are closed.
WAIt wait-time Sets a maximum time interval the QUIesce command should wait for all socket descriptors to close. wait-time is a positive number between 1 and 32767. When this time interval is exhausted or when the quiesce request is canceled, the following occurs, depending on the KEEp or FORce option specified on the WAIt clause:
If KEEp is specified (default value), TCP/IP is reenabled in the same way as using a DCMT VARY TCP/IP STATUS ON KEEP command.
If FORCe is specified, TCP/IP is disabled in the same way as using a DCMT VARY TCP/IP STATUS OFF FORCE command.
Immediately terminates TCP/IP support in the DC/UCF system. All the LISTENER and DDSTCPIP PTERM's are closed, including all active sockets. Applications using sockets receive an error code on their next socket function call.
Cancels an outstanding DCMT VARY TCP/IP STATUS OFF QUIESCE command. The KEEp or FORCe option overwrites the KEEp or FORCe option specified on the DCMT VARY TCP/IP STATUS OFF QUIESCE command.
Switches the TCP_NODELAY socket global option ON or OFF.
Overwrites the default stack assigned by the system. Changing the default stack dynamically has no effect on the existing sockets. Only the newly created sockets that use the default stack affinity are affected. This option is useful only in a multiple stack environment.
Includes (activates) a TCP/IP stack in the DC/UCF system. stack-name is the job name of a TCP/IP stack and is limited to eight characters. This option is used differently depending on the operating system:
If stack-name is active in the operating system, it becomes active in the CA IDMS system; if not, it remains inactive in the DC/UCF system.
Excludes a TCP/IP stack that is included (active) in the DC/UCF system. stack-name is the job name of a TCP/IP stack. The stack-name is limited to eight characters.
Specifies the maximum number of sockets that can be created globally in the DC/UCF system. max-socket is a positive number between 1 and 65535. The maximum number of sockets that can be created in one address space can also be limited by the operating system, for example, through USS definitions under z/OS.
Specifies the maximum number of sockets that can be created by a single task in the DC/UCF system. The maximum value and the default value for this parameter are both equal to the value assigned at runtime to max-socket. If the max- socket-per-task value is greater than max-socket, it is truncated.
Refreshes the internal copy of the services file in memory after the services file has been updated.
Note: To make updates to the services file while the data set is currently defined in the startup JCL with the DISP=SHR option, the file should be allocated as a member from a PDS.
Changes the case sensitivity that applies to the services names specified on the GETSERVBYNAME function calls.
(z/OS only) Refreshes the list of stacks currently defined to CINET without the need to stop the TCP/IP support in the DC/UCF system. This command is accepted only when the TCP/IP status is ON.
If a new stack has been added to the list, it will not be activated in the DC/UCF system automatically. You must issue an explicit DCMT VARY TCP/IP INCLUDE STACK command to activate it in the DC/UCF system. The DCMT DISPLAY TCP/IP STACK TABLE shows the value New in the Active column from the corresponding entry.
Usage
Specifying new socket values
New values can be assigned to max-sockets and max-socket-per-task when TCP/IP is currently enabled in the DC/UCF system, only if the new value is lower than the corresponding value at the time TCP/IP was enabled. In the other case, TCP/IP must be recycled. That is, disabled first and then reenabled.
The checks on the maximum number of sockets allowed are always done when a new socket is created. No sockets are forcibly closed if the maximum number of sockets is set to a lower value.
More Information
For more information about DCMT commands, see the CA IDMS System Tasks and Operator Commands Guide.
The DCMT HELP command has been enhanced to display a help screen of the DCMT DISPLAY TCP/IP and DCMT VARY TCP/IP syntax.
Syntax
►►─── DCMT ─┬───────────────────┬─────────────────────────────────────────────► └─ broadcast-parms ─┘ ►─────── Help ┬─ . . . ──────────────────────────┬───────────────────────────► └─ TCP/ip or TCPip ────────────────┘
Parameters
Displays syntax for the HELP command.
Displays the TCP/IP help screen.
More Information
For more information about the DCMT HELP command, see the CA IDMS System Tasks and Operator Commands Guide.
CA IDMS is enhanced with a new TCP/IP socket option, TCP_NODELAY. The TCP_NODELAY socket option disables the Nagle's algorithm, enabling two consecutive SEND socket functions to be executed without any delay between the two sends.
You can set the TCP_NODELAY socket option using the following methods:
The SETSOCKOPT socket function is described below. The two other methods are described in New TCP/IP System Entity.
Use the SETSOCKOPT socket function to explicitly set the TCP_NODELAY socket option for a user application, thereby overriding the default value.
|
EQUate Symbol |
Field Name |
Description |
|---|---|---|
|
TCP@NODL |
SOCKET-SOCKOPT-NODELAY |
TCP_NODELAY option |
This section describes only the new option. For more information about the SETSOCKOPT socket function, see the CA IDMS Callable Services Guide.
Notes
CA IDMS is enhanced to support the following socket functions:
These new socket functions provide the following capabilities:
These new functions allow a user application to be independent of a specific port number. A user application program can make use of a service name and dynamically retrieve the corresponding port number to use at runtime using the GETSERVBYNAME socket function. The services file identified by the TCP/IP SYSGEN statement is used to resolve this mapping.
GETSERVBYNAME takes a service name and a protocol and tries to resolve them using the services file. If successful, it returns the information in a SERVENT structure.
Assembler
Label #SOCKET GETSERVBYNAME,
RETCODE=return-code,
ERRNO=errno,
RSNCODE=reason-code,
SERVNAME=service-name,
SERVNAML=service-name-length,
PROTNAME=protocol-name,
PROTNAML=protocol-name-length,
SERVENTP=serventp,
PLIST=parameter-list-area,
RGSV=(rgsv)
List of USING Parameters
SOCKET-FUNCTION-GETSERVBYNAME, return-code, errno, reason-code, service-name, service-name-length, protocol-name, protocol-name-length, serventp
|
Parameter |
Description |
|---|---|
|
service-name |
The name of an area containing the name of the service to resolve. |
|
service-name-length |
The name of a fullword field containing the length of service-name. service-name-length can be specified as an absolute expression. The maximum value for this parameter is 256. |
|
protocol-name |
The name of an area containing the name of the protocol to use. |
|
protocol-name-length |
The name of a fullword field containing the length of protocol-name. protocol-name-length can be specified as an absolute expression. The maximum value for this parameter is 256. |
|
serventp |
The name of a fullword field where the system returns the address of a SERVENT structure containing the information about the service. |
Note: For more information about the SERVENT structure, see Socket Structure Description.
If it is defined as INSENSITIVE, the internal services resolver always tries to first retrieve the service-name and protocol-name as they are coded in the socket function call. If they are not found, the first entry where the uppercase versions of the service names and protocol names match are returned. In all cases, all the strings returned in the SERVENT structure are always coded as they appear in the services file.
GETSERVBYPORT takes a port number and a protocol number and tries to resolve them using the services file. If successful, it returns the information in a SERVENT structure.
Assembler
Label #SOCKET GETSERVBYPORT,
RETCODE=return-code,
ERRNO=errno,
RSNCODE=reason-code,
PORT=port-number,
PROTNAME=protocol-name,
PROTNAML=protocol-name-length,
SERVENTP=serventp,
PLIST=parameter-list-area,
RGSV=(rgsv)
List of USING Parameters
SOCKET-FUNCTION-GETSERVBYPORT, return-code, errno, reason-code, port-number, protocol-name, protocol-name-length, serventp
|
Parameter |
Description |
|---|---|
|
port-number |
The name of a fullword field containing the port-number to resolve. |
|
protocol-name |
The name of an area containing the name of the protocol to use. |
|
protocol-name-length |
The name of a fullword field containing the length of protocol-name. protocol-name-length can be specified as an absolute expression. The maximum value for this parameter is 256. |
|
serventp |
The name of a fullword field where the system returns the address of a SERVENT structure containing the information about the service. |
Note: For more information about the SERVENT structure, see Socket Structure Description.
If it is defined as INSENSITIVE, the internal services resolver always tries to first retrieve the service-name and protocol-name as they are coded in the socket function call. If they are not found, the first entry where the uppercase versions of the service names and protocol names match are returned. In all cases, all the strings returned in the SERVENT structure are always coded as they appear in the services file.
IOCTL controls certain characteristics of a socket. Depending on the command, it can retrieve or set control information.
Assembler
Label #SOCKET IOCTL,
RETCODE=return-code,
ERRNO=errno,
RSNCODE=reason-code,
SOCK=socket-descriptor,
COMMAND=command,
ARGUMENT=argument,
ARGUMENL=argument-length,
PLIST=parameter-list-area,
RGSV=(rgsv)
List of USING Parameters
SOCKET-FUNCTION-IOCTL, return-code, errno, reason-code, socket-descriptor, command, argument, argument-length
|
Parameter |
Description |
|---|---|
|
socket-descriptor |
The name of a fullword field containing the socket-descriptor to process. |
|
command |
The name of a fullword field containing the command to perform on the socket. command can be specified as an absolute expression. |
|
argument |
The name of a fullword field containing the address of the argument area that is used by the corresponding command. The argument area usually contains input and output fields. |
|
argument-length |
The name of a fullword field that contains the length of the argument area. |
The different commands and arguments allowed usually depend on the operating system where the CA IDMS system is running. For a full description of these parameters, see the corresponding socket API manual.
z/VSE systems: The IOCTL function is not supported.
The following table lists the commands that can be specified. The EQUate symbol is generated by #SOCKET macro and the field names are associated with the SOCKET-MISC-DEFINITIONS-2 record.
|
EQUate Symbol |
Field Name |
Description |
|---|---|---|
|
IO@NREAD |
SOCKET-IOCTL-FIONREAD |
Sets or resets socket in non-blocking mode |
|
IO@NBIO |
SOCKET-IOCTL-FIONBIO |
Retrieves the number of readable bytes available |
|
IO@CTTLS |
SOCKET-IOCTL-SIOCTTLSCTL |
Allows an application to query or control AT-TLS |
PL/I programs: The SOCKET_MISC_DEFINITIONS_2 is used and the dashes are replaced by underscores.
More information:
For more information about socket functions, see the CA IDMS Callable Services Guide.
On z/OS, the GETADDRINFO and GETNAMEINFO socket functions are supported by the operating system. On z/VSE and z/VM, the GETADDRINFO and GETNAMEINFO socket functions are now supported by the CA IDMS DNS and Services Resolvers.
More information:
For more information about the CA IDMS DNS and Services Resolvers, see the CA IDMS System Operations Guide.
The SERVENT structure is returned by the GETSERVBYNAME and GETSERVBYPORT function calls.
|
Field |
Description |
|---|---|
|
Service name |
Address of a service name (null-terminated string). |
|
Aliases |
Address of a zero-terminated array of pointers to aliases, which are null-terminated strings. |
|
Port |
Port number associated with a service. |
|
Protocol |
Address of the protocol associated with a service (null-terminated string). |
CA IDMS is enhanced to provide a new access method for CA IDMS DDS using the TCP/IP protocol through the SOCKET interface. This enhancement improves the performance of database requests to geographically distributed databases.
You can define the DDS connectivity using the following methods:
Use the system generation NODE statement to specify the use of TCP/IP to access a target node in the DC/UCF communications network.
Syntax
ADD/MODIFY/DELETE NODE Statement
►►─┬─ ADD ────┬─ NODe nodename ──────────────────────────────────────────────► ├─ MODify ─┤ └─ DELete ─┘ ►──┬─ . . . ──┬─────────────────────────────────────────────────────────────► ├─ TCP/ip ─┤ └─ TCPip ──┘
Parameters
(DDS users only) Specifies that the TCP/IP protocol is used to access the named node.
More Information
For more information about the system generation NODE statement, see the CA IDMS System Generation Guide.
In support of DDS communications through TCP/IP, a new DDSTCPIP type of PTERM can now be associated with a SOCKET line and the maximum number of connections can be specified for a LISTENER PTERM.
In support of port number independence, the LISTENER PTERM statement has also been enhanced to allow the specification of a service name in place of a port number.
Use the DDSTCPIP PTERM statement in a SOCKET line to define the remote system where the target node is running.
Syntax
►►─ TYPe is DDSTCPIP ──────────────────────────────────────────────────────► ►─ TARget ┬ ADDress is 'target-ip-address'┬───────────────────────────────► └ NAMe is target-host-name ─────┘ ►─ TARget PORt is target-port-identifier ─────────────────────────────────► ►─┬─────────────────────────────────┬─────────────────────────────────────► └ IP STAck NAMe is stack-ip-name ─┘ ►─┬─────────────────────────────────────────────────────────────────┬─────► └ PORt RANge is ─┬ OFF ◄──────────────────────────────────────────┤ └ start-port-number ─┬ THRu ───┬ end-port-number ┘ └ THRough ┘ ►─┬─────────────────────────────────┬─────────────────────────────────────► └ IDLe INTerval is idle-interval ─┘ ►─┬──────────────────────────────────────────────────────┬────────────────► └ MAXimum NUMber of CONnections is ─┬ OFF ◄────────────┤ └ max-number-conn ─┘ ►─┬──────────────────────────────────────────────────────┬────────────────►◄ └ NUMber of PERmanent CONnections is perm-conn-number ─┘
Parameters
The target-ip-address and target-host-name parameters are mutually exclusive. You must specify at least one of these parameters in the definition of a DDSTCPIP type PTERM.
Specifies the IP address of the target system enclosed in single quotes. The IP address limit depends on whether IPv4 or IPv6 is used: IPv4 is 15 characters; IPv6 is 45 characters.
Specifies the host name of the target system. The maximum host name length is 64 characters.
Specifies the number of the target port or a service name. If target-port-identifier is a port number, it must be a positive number, between 1 and 65535. If target-port-identifier is a service name, it is limited to 32 characters and must be the name of a service in the services file with an associated protocol of TCP.
Specifies the job name of the TCP/IP stack to use in the local system. The job name is limited to 8 characters. Specify an empty string value (two single-quotes) to remove an IP STACK NAME definition.
Defines a range of port numbers that are used to BIND the local sockets explicitly. Each time a new connection is established, the first free port from the range is selected and associated (bound) with the corresponding socket. If no free port is found, the request is aborted.
The default value is OFF, indicating that the operating system will select a free port from the pool and bind the socket implicitly during the connect processing. start-port-number and end-port-number are positive numbers between 1 and 65535. start-port-number must be lower than or equal to end-port-number.
Defines the time interval a non-permanent connection stays in an idle state after the corresponding DDS request has finished. This allows the same connection to be reused if a new DDS request comes in before the timeout expires.
idle-interval is a positive number between 0 and 32767. The default value is 0.
Defines the maximum number of active connections allowed from the local system.
max-number-conn is a positive number between 1 and 65535. The default value is OFF, indicating that the maximum number of connections is unlimited.
Note: The maximum number of connections depends on the number of free BULK PTERMs in the SOCKET line on the target (remote) system.
Defines the number of permanent connections that can exist between the host and the target systems.
perm-conn-number is a positive number between 0 and 65535. The default value is 0, indicating that permanent connections are not needed. In this case, the connections are always established dynamically when a new DDS request arrives.
Use the LISTENER PTERM statement in a SOCKET line to control the number of active BULK PTERMs that can be started from a specific LISTENER PTERM and to alternatively specify a service name instead of a port number.
Syntax
►►── TYPe is LISTENER ─────────────────────────────────────────────────────► ►─┬──────────────────────────────────────────────────────┬────────────────► └ MAXimum NUMber of CONnections is ─┬ OFF ◄────────────┤ └ max-number-conn ─┘ ►─── PORT is listener-port-identifier ────────────────────────────────────► ►─── . . . ───────────────────────────────────────────────────────────────►
Parameters
Defines the maximum number of active connections that can be started from the corresponding listener program, that is, the maximum number of active BULK PTERMs allocated by the specific LISTENER. When the number of connections reaches the value specified for max-number-conn, any new connection accepted by the listener program will be rejected.
max-number-conn is a positive number between 1 and 65535. The default value is OFF, indicating that the maximum number of connections is unlimited.
Specifies the number of the listener port or a service name. If listener-port-identifier is a port number, it must be a positive number between 1 and 65535. If listener-port-identifier is a service name, it is limited to 32 characters and must be the name of a service in the services file with an associated protocol of TCP.
For more information about the system generation PTERM statement, see the CA IDMS System Generation Guide.
The DCMT VARY PTERM command has been enhanced to allow altering the attributes specific to a DDSTCPIP PTERM.
Note: Only a few of the parameters can be changed without requiring the corresponding PTERM to be varied OFFLINE first. For more information, see Usage.
Syntax
►─── DCMT ─┬───────────────────┬───────────────────────────────────────────► └─ broadcast-parms ─┘ ►─── Vary PTErminal physical-terminal-id ──────────────────────────────────► ►─┬─ . . . ──────────────────────────────────────────────────────────────┬─►◄ ├─ IDLe INTerval idle-interval ────────────────────────────────────────┤ ├─ MAXimum CONnections max-number-conn ────────────────────────────────┤ ├─ PERmanent CONnections perm-conn-number ─────────────────────────────┤ ├─ PORt RANge ─┬─ OFF ◄──────────────────────────────────────────────┬─┤ │ └─ start-port-number ─┬─ THRU ────┬─ end-port-number ─┘ │ │ └─ THRough ─┘ │ ├─ TARget ─┬─ ADDress 'target-ip-address' ─┬───────────────────────────┤ │ └─ NAMe 'target-host-name' ─────┘ │ └─ TARget PORt target-port-identifier ─────────────────────────────────┘
Parameters
Defines the time interval a non-permanent connection stays in an idle state after the corresponding DDS request has finished. This allows the same connection to be reused if a new DDS request comes in before the timeout expires.
idle-interval is a positive number between 0 and 32767. The default value is 0.
For a DDSTCPIP type PTERM, defines the maximum number of active connections allowed from the local system. For a LISTENER type PTERM, defines the maximum number of active BULK PTERM that can be started from that listener.
max-number-conn is a positive number between 1 and 65535. The default value is OFF, indicating that the maximum number of connections is unlimited.
Note: The maximum number of connections depends on the number of free BULK PTERMs in the SOCKET line on the target (remote) system.
Defines the number of permanent connections that can exist between the host and the target systems.
perm-conn-number is a positive number between 0 and 65535. The default value is 0, indicating that permanent connections are not needed. In this case, the connections are always established dynamically when a new DDS request arrives.
Defines a range of port numbers that are used to BIND the local sockets explicitly. Each time a new connection is established, the first free port from the range is selected and associated (bound) with the corresponding socket. If no free port is found, the request is aborted.
The default value is OFF, indicating that the operating system will select a free port from the pool and bind the socket implicitly during the connect processing. start-port-number and end-port-number are positive numbers between 1 and 65535. start-port-number must be lower than or equal to end-port-number.
Specifies the IP address of the target system enclosed in single quotes. The IP address limit depends on whether IPv4 or IPv6 is used: IPv4 is 15 characters; IPv6 is 45 characters.
Specifies the host name of the target system. The maximum host name length is 64 characters.
Specifies the number of the target port or a service name. If target-port-identifier is a port number, it must be a positive number between 1 and 65535. If target-port-identifier is a service name, it is limited to 32 characters and must be the name of a service in the services file with an associated protocol of TCP.
Usage
LISTENER or DDSTCPIP type PTERM OFFLINE Requirements
The following table contains the parameters that are accepted for a LISTENER or DDSTCPIP type PTERM. The last column indicates if the owning PTERM must be OFFLINE to allow the corresponding parameter to be changed dynamically.
|
|
LISTENER PTERM |
DDSTCPIP PTERM |
PTERM OFFLINE |
|---|---|---|---|
|
BACKLOG |
X |
|
X |
|
IDLE INTERVAL |
|
X |
|
|
MAXIMUM CONNECTIONS |
X |
X |
|
|
MODE SYSTEM/USER |
X |
|
X |
|
PARM |
X |
|
X |
|
PERMANENT CONNECTIONS |
|
X |
|
|
PORT |
X |
|
X |
|
PORT RANGE OFF |
|
X |
|
|
PORT RANGE <range> |
|
X |
* |
|
TARGET ADDRESS |
|
X |
X |
|
TARGET NAME |
|
X |
X |
|
TARGET PORT |
|
X |
X |
|
TASK |
X |
|
X |
|
TCP/IP ADDRESS |
X |
|
X |
|
TCP/IP NAME |
X |
|
X |
|
TCP/IP STACK |
X |
X |
X |
If the corresponding PTERM is ONLINE, the <range> value can be changed dynamically only if the port range parameter was not assigned to OFF at the time the PTERM was opened.
More Information
For more information about the DCMT VARY PTERM command, see the CA IDMS System Tasks and Operator Commands Guide.
Use the DCMT DISPLAY DDS command to display general information about the DDS network or about a particular DDS line or physical terminal. It can now display a DDSTCPIP type PTERM, if present.
Syntax
►►─── DCMT ┬───────────────────┬──────────────────────────────────────────────► └─ broadcast-parms ─┘ ►─── Display DDS ┬───────────────────────────────────────┬───────────────────►◄ ├─ LINe line-id ────────────────────────┤ └─ PTErm physical-terminal-id ┬───────┬─┘ └─ ALL ─┘
Parameters
Displays information for the specified DDS physical terminal.
The ID of a physical terminal defined on the system generation PTERM statement.
ALL (DDSTCPIP type PTERM only) Displays a list of all TCP/IP connections with its owning LTERM, the corresponding expiration time (if the connection is in the idle list only), and the local port used.
Examples
DCMT DISPLAY DDS
*** Display DDS *** Line PTerm Node Name Weight BLKSIZE DDSVTAM PDDSVT99 30 8192 PDDSVT73 12 28000 PDDSVT74 12 16500 PDDSVX73 12 28000 PDDSVX74 12 16500 PDDSVX71 12 8176 PDDSVT71 SYSTEM71 12 8192 Line PTerm Node Name SOCKET SY71CA31 SYSTEM71 SY71CA11
DCMT DISPLAY DDS PTERM ddstcpip-pterm-id ALL
PTERM definitions Run-time information ====================================== ====================================== PTERM name SY71CA31 Target IDMS node SYSTEM71 LTERM name SY71CA31 Number connections requested 54 Line name SOCKET Number connections created 4 IP stack name *DEFAULT Number connections active 4 Target host USILCA31 HWM connections in-use 4 Target port 3771 Number connections found in Port range OFF * permanent list 45 Maximum connections OFF * idle list 5 Permanent connections 1 Number retry for free port 0 Idle interval 60 Number connections rejected * max connection 0 * no free port 0 * socket error 0 TCP/IP connections Owning LTERM Expiration time Local port ================== ============ =============== ========== Control connection SY71CA31 n/a 2138 In-use list LD000001 n/a 2152 Permanent list SY71CA31 n/a 2161 Idle list SY71CA31 45 2165
Usage
DCMT DISPLAY DDS PTERM ddstcpip-pterm-id ALL displays global information and statistics about a specific DDSTCPIP type PTERM. The display includes the following PTERM definitions and run-time and ALL option information:
|
Field |
Value |
|
PTERM Definitions |
|
|
PTERM name |
Name of the DDS physical terminal |
|
LTERM name |
Name of the DDS logical terminal |
|
Line name |
Name of the line with which the physical terminal is associated |
|
IP stack name |
Job name of the TCP/IP stack in the local system |
|
Target host |
Host name of the target system |
|
Target port |
Target port number or service name |
|
Port range |
Range of port numbers |
|
Maximum connections |
Maximum number of active connections allowed from the local system |
|
Permanent connections |
Number of permanent connections between the host and the target systems |
|
Idle interval |
Time interval that the non-permanent connection stays in an idle state after the corresponding DDS request has finished |
|
Run-time Information |
|
|
Target IDMS node |
Name of the CA IDMS node in the target (remote) system |
|
Number connections requested |
Number of DDS requests that have already been processed to the target system. Each DDS request is processed through one TCP/IP connection. |
|
Number connections created |
Number of connections that have been created to satisfy all the DDS requests |
|
Number connections active |
Number of connections currently active between the client system and the remote system |
|
HWM connections in-use |
Maximum number of connections that are processing DDS requests concurrently |
|
Number connections found in permanent list/idle list |
Number of times a free connection could be found in the permanent list or idle list to process a DDS request. A small number in these fields in comparison with the value displayed for the Number connections created field indicates that you may want to increase the definitions for NUMber of PERmanent CONnections or IDLe INTerval parameters in SYSGEN. |
|
Number retry for free port |
Number of times the system had to retry to find a free port number from the port range defined at the PTERM level. This occurs only when a port from the port range is in use by another application in the system. |
|
Number connections rejected |
Number of times the creation of a connection has been rejected. A rejection is caused by one of the following:
|
|
ALL Option Information |
|
|
TCP/IP connections |
A type or list owning the connection as follows:
|
|
Owning LTERM |
Name of the LTERM owning the connection |
|
Expiration time |
This field applies only to connections belonging to the Idle list. It indicates the remaining time, in seconds, before the corresponding connection is closed. The maximum value for this field is the value assigned to the IDLe INTerval parameter in SYSGEN. |
|
Local port |
Port number used at the local side of the connection |
More Information
For more information about the DCMT DISPLAY DDS command, see the CA IDMS System Tasks and Operator Commands Guide.
The UCF DC front-end enables a terminal on one DC system to execute tasks on a second DC system.
The ACCTYPE parameter on the #UCFOPTS macro can now accept TCP/IP parameters.
Syntax
►►─── label #UCFOPTS ──────────────────────────────────────────────────────────► ►─┬─ . . . ───────────────────────────────────┬───────────────────────────────► └─ NODE = nodename ,ACCTYPE= ─┬─ CCI ───────┤ ├─ VTAM ──────┤ ├─ TCP/IP ────┤ └─ TCPIP ─────┘
Parameters
Identifies the back-end when access is via DC/DDS:
Note: This parameter applies only to DDS.
More Information
For more information about UCF support for a DC front-end, see the CA IDMS System Operations Guide.
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Copyright © 2009 CA.
All rights reserved.
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