MAXHNRES start option


   .-MAXHNRES--=--100----------------------.   
>>-+---------------------------------------+-------------------><
   '-MAXHNRES--=--max_hostname_resolutions-'

range:

2-500

Specifies the maximum number of host name resolution requests that can run concurrently. This start option controls host name resolution requests for the following functions:

EE line activation
Dialing an EE switched PU
Host name filters specified on D NET,EE commands
Host name filters specified on D NET,EEDIAG commands

The MAXHNRES start option is closely related to the DLRTCB start option. The MAXHNRES start option controls the number of subtasks that VTAM® allows for Enterprise Extender host name resolution requests. The MAXHNRES start option value is internally added to the value of the DLRTCB start option value, but the resulting value cannot exceed the DLRTCB upper limit. This enables VTAM to govern the number of TCBs used to perform EE host name resolutions.

Restriction: The DLRTCB and MAXHNRES start options cause control blocks to be built below the 16-megabyte line. Therefore, the availability of storage might limit the value that you can code, and conversely, the value you code might impact the availability of the storage.

Results:

When the total number of resolver requests for D NET,EE and D NET,EEDIAG commands reaches the MAXHNRES value, all subsequent D NET,EE and D NET,EEDIAG commands that specify host name filters are rejected until some of the previous resolver requests complete.
The number of concurrent requests allowed for EE display command processing is limited to 80% of the MAXHNRES value. This ensures that 20% of the task control blocks remain available for line activation or dial processing.
When a D NET,EE or D NET,EEDIAG command is entered with both a local and remote host name filter, VTAM initiates two host name resolution requests. Therefore, one display command can account for two host name resolutions that run concurrently.