SNALINK parameters

The system parameters required by SNALINK are passed by the PARM parameter on the EXEC statement of the SNALINK cataloged procedure. The parameters are order-dependent and appear in the following list:

DEBUG

Enables detailed tracing into an internal buffer. If specified, it must be the first parameter in the list.

TCP=‘tcpid’

Specifies the name of the TCP/IP address space, in quotation marks.

APPLID=‘applid’

Specifies the name of the VTAM® application (LU name), in quotation marks, that SNALINK uses for this system.

max_ru_size

This parameter is optional, and is the maximum RU size in hexadecimal. The default size is 88 (in form mn). Set max_ru_size to specify the maximum request or response unit (RU) size that SNALINK sends. The value is of the form mn, where m is between 8 and F, and n is between 0 and F. The corresponding maximum RU size is m2ⁿ (m multiplied by 2 to the power of n). Use the largest size that works on your SNA network, to provide the best performance and the least overhead. See z/OS Communications Server: SNA Programming for more information about this parameter as well as z/OS Communications Server: IP Configuration Guide.

max_session

The maximum number of sessions; a decimal value from 1 to 9 999. The default value is 6. To use different values for max_session, you also have to specify the max_ru_size.

retry

The delay time for VTAM to try sense codes again. It has the following format: hhmm. Where:

hh

Hours 0 - 24

mm

Minutes 0 - 59

For example:

• 0005 is a 5-minute delay.
• 0200 is a 2-hour delay.
• 1030 is a 10-hour and 30-minute delay

The default delay is 15 minutes and the maximum delay is 24 hours. To use a different retry interval, you must specify both max_ru_size and max_session.

session_type

Defines the SNALINK communication session mode. The session_type can have the values of SINGLE, DUAL, or be omitted. If the parameter is omitted, session_type defaults to DUAL. If the session_type is set to SINGLE, SNALINK creates a single duplex session. If DUAL is specified, SNALINK creates two sessions, a send session and a receive session. Like max_session and retry, if session_type is specified, you must also specify the previous parameters.

NCPROUTE and 3745 Communication Controller Ethernet links require session_type of SINGLE.