363-206-295
Administration and Provisioning
Issue 1
December 1997
8-5
Controller Maintenance
8
The controller for the DDM-2000 OC-12 Multiplexer consists of the SYSCTL and
OHCTL circuit packs. The SYSCTL circuit pack provides CIT interfaces and
coordinates protection switching, as well as all shelf maintenance and
provisioning activities. The OHCTL circuit pack provides an X.25 interface and a
communications channel to remote shelves via the DCC bytes in the OC-N
section overhead. Both circuit packs have a processor and both have volatile
random access memory (RAM) and nonvolatile memory.
The DDM-2000 OC-12 Multiplexer is designed so that SYSCTL failures do not
affect transmission. That is, no hits or errors will occur on any traffic as a result of
a SYSCTL circuit pack failure. A SYSCTL failure does result in the loss of
automatic protection switching. However, if a transmission circuit pack fails before
a SYSCTL failure, the protection switch will remain effective during the SYSCTL
failure and service is preserved. This means that if an active transmission circuit
pack should fail while the SYSCTL is failed, a protection switch cannot be done
and service carried by the failed circuit pack will be affected.
Memory Administration
8
All transmission affecting parameters that are set by software are stored in
nonvolatile memory on the SYSCTL circuit pack and on the appropriate
transmission circuit packs. When the shelf is powered up or the SYSCTL circuit
pack is replaced, the shelf's transmission values are automatically uploaded to the
SYSCTL. When a transmission circuit pack is replaced, provisioning data stored
on the SYSCTL is automatically downloaded to the replacement circuit pack.
Manual action is not required to maintain system provisioning after a circuit pack
is replaced.
Certain non-service-affecting provisioned data, such as alarm delay are stored
only on the SYSCTL circuit pack. This means that when a SYSCTL circuit pack is
replaced, the new SYSTCL circuit pack should be initialized by pressing the INIT
button during the 10-second interval while the CR alarm LED is flashing after the
SYSCTL circuit pack is inserted. This action is the same as entering the
init-
sys:sysctl
command which sets the SYSCTL circuit pack parameters to their
default values. Refer to the
init-sys
command in Section 11, "Commands and
Reports," and to "Install or Replace SYSCTL," in the TOP section of this manual
(Volume II). If parameters other than the default values are needed, the values
must be entered using the CIT. If the INIT function is not performed, whatever
values that are stored in nonvolatile memory on the new SYSCTL circuit pack are
used. Failure to follow the proper procedure may not cause transmission errors or
loss of service but could affect maintenance. For example, an invalid TID could
produce confusing TL1 reports to the OS.
