Справочник Пользователя для StorageTek 6

1st ed., 6/30/04 - 312579601

Communications services are set or changed by the Communications Path (COMMPath) 
command and control statement. This command specifies host, communication method, 
LMU paths and VTAM path name for the associated host. The communication path 
definitions can be modified at any time during library operation without terminating the 
HSC. 

The COMMPath command and control statement sets up a table of definitions for the host 
that is executing the command. Each host’s table must contain a list of path definitions for 
itself and a separate list for each defined host. Therefore, on each host, the command must 
be issued once to define the paths for itself, once to define the paths for a second host, 
once to define the paths for a third host, and so on, until all hosts are defined. 

For example, the library is operating in an environment with three hosts: Host 0, Host 1, 
and Host 2. The COMMPath command must be issued three times on each host. The table 
of definitions for Host0 must contain a list of paths for Host 0, a list for Host 1, and a list 
for Host 2. The same is true for Host 1 and Host 2.

For one host to communicate with another, they must have matching entries in their 
respective lists of defined paths. The highest-performance method that is common to two 
hosts is selected as the current method of communications between the two. A host can 
use one method of communications with a second host, and a different method of 
communications with a third host. 

Figure 9 illustrates how different communication methods can be used between multiple 
hosts.

 

C26184

CDS

COMMUNICATIONS

LMU

COMMUNICATIONS

HOST 0

METHODS

VTAM

CDS

HOST 1

METHODS

LMU
CDS

HOST 2

METHODS

VTAM

LMU
CDS

VTAM

COMMUNICATIONS

EACH PAIR OF HOSTS COMMUNICATE USING THE

HIGHEST PERFORMANCE METHOD DEFINED TO BOTH