General configuration considerations for improved error recovery performance
Careful use of the ONLINE general configuration parameter is necessary
to avoid unnecessary communications error recovery. Most communications configuration
objects are created with the ONLINE parameter default set to *YES (except
for PPP lines, the ONLINE parameter is set to *NO). Consider the setting
of the ONLINE parameter in any of the following:
- CRTCTLxxx commands
- CRTDEVxxx commands
- CRTLINxxx commands
- CRTNWIxxx commands
- CRTNWSD command
Note:
For the network server (NWS) command, you
should set the ONLINE parameter value to *NO. If network server descriptions
are brought online during the system initial program load (IPL), important
system jobs might be held up and unavailable for other work.
When choosing how to set the ONLINE parameter, consider the following:
- Limit the configuration objects that vary on during IPL with the ONLINE
parameter set to *YES. These objects should be only those like tape drives,
CD-ROM drives, and selected local workstations that are critical to getting
your applications up and available for general system use.
- Place critical users in a subsystem group, and vary on configuration objects
for this group by using the ONLINE parameter that is set to *YES. This allows
critical users to get back online sooner.
- For noncritical users, vary on configuration objects at a later point
by setting the ONLINE parameter to *NO. Use a CL program or change the system
startup program to manage vary on of the remaining configuration objects.
- For controllers on local area networks (LAN), set the auto-configuration
parameter (AUTOCRTCTL) to *YES on the appropriate LAN controller descriptions.
Let the system vary these controller descriptions on as needed.
- Whenever possible, avoid varying on any configuration that would fail
in attempts to connect to remote systems. For example, avoid varying on controllers
with a link type of *LAN that have an initial connection of *DIAL, when remote
systems are not available. Personal computers on local area networks (LANs)
typically do not respond to connection attempts.
See the following references for more detail:
book.