Configuring and Managing Host-Based X.25 Links - Edition 6 (36939-90057)

Managing Networks with DTCCNTRL
Dynamic Configuration
Chapter 7
153
Dynamic Configuration
Dynamic Configuration enables you to change the configuration of the DTS subsystem
by applying the configuration changes made in NMMGR without rebooting the system.
Such configuration changes include adding or deleting ldevs, adding or deleting DTCs,
modifying most parameters of profiles, or DTCs, changing the number of non-nailed
ldevs. See Table 7-1 for a complete list of changes that can be made dynamically. (Some
changes will require additional action, such as resetting the DTC, before the change is
completed.)
NMMGR can keep up to 70 changes. This means that you can change a maximum of 70
different screens before you invoke DTCCNTRL. After the 64th change NMMGR displays a
warning that tells you the limit is near. If more than 70 changes are made NMMGR
warns that the current change will not take effect using DTCCNTRL. After DTCCNTRL is
invoked and the changes were successful, NMMGR can again keep up to 70 new
changes. Those changes that were not successful will be saved so they can be retried at a
later time. When a new DTC is added NMMGR considers this to be one change even if
you save data on many screens to configure this DTC.
CAUTION If more than 70 changes are made without invoking DTCCNTRL, then dynamic
configuration will be disabled until the DTC Subsystem is shut down and restarted. This
is necessary because DTCCNTRL will not know about any changes made after 70 and that
can cause dynamic configuration to fail.
All operations that delete ldevs are non-destructive. This means that if an ldev to be
deleted is in use, then the delete is not performed. You must take the appropriate action
to free the device. For example, you must stop the spooler on a spooled serial printer or
log off the session on a terminal ldev. If multiple ldevs are deleted, then only free ldevs
are deleted. Those ldevs that were not free will be processed again the next time
DTCCNTRL is invoked. If PAD ldevs are deleted on a card all ldevs that are to be deleted
must be free for the operation to complete. A change in the PAD Device name is
processed as a delete, then add of an ldev.
Some changes may affect more than one user. Usually this may happen when the change
is to a DTC characteristic such as adding a card. This is because the DTC will need to be
powered off or reset. Users on other DTCs are not affected.
Some changes will require additional steps to complete once DTCCNTRL has made the
desired changes. These possible additional steps are: logoff any sessions or close any jobs
that access the changed devices, stop and restart the spooler if the device is a printer,
stop and the start X.25/PADSUP, reboot or reset the DTC. DTCCNTRL will display a
message when these steps are necessary and tell you which DTCs are affected.
Refer to Table 7-1 for a list of configuration changes that can be modified dynamically.