Clock Control Unit Replacement; Overview Of The Clku - Fujitsu SPARC Enterprise M8000 Service Manual

16
C H A PT E R

Clock Control Unit Replacement

This chapter explains the replacement procedure for the clock control unit (CLKU).
It covers the following:
Section 16.1, "Overview of the CLKU" on page 16-1
■
Section 16.2, "Cold Replacement" on page 16-4
■
Cold replacement is the only swapping method that can be used for the CLKU. For the
definition of the swapping method, see
page
16.1

Overview of the CLKU

This section provides an overview of the CLKU and describes its mounting locations.
The CLKU is mounted only in the M9000 server, and it supplies clock signals to
CPU/memory board unit (CMU) and crossbar units (XBUs). CLKUs are duplicated, but
active maintenance cannot be performed on them. For the M9000 server with the expansion
cabinet, there are cables available for connecting the clocks in the base cabinet to those in the
extension cabinet.
FIGURE 16-1
M9000 server (base cabinet) and M9000 server (with the expansion cabinet), respectively.
4-2.
and
FIGURE 16-2
Section 4.1, "Types of Replacement Procedures" on
show the CKLU mounting locations in the cabinets of the
16-1