Specifications

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Cisco MGX 8850 (PXM45) and MGX 8950 Software Configuration Guide
Release 3, Part Number 78-14788-01 Rev. C0, January 2004
Chapter 7 Switch Operating Procedures
Diagnostics Support MGX 8850 and MGX 8950 Switches
The MGX 8850 and MGX 8950 switch support both online and offline diagnostics.
• Online diagnostics tests run in the background while a card is in an operational state. These tests are
non-intrusive and run with minimal overhead. Online diagnostics can be used to detect hardware
errors diagnosis. Its goal is to monitor any potential errors at a card level while a card is in normal
operation. You can stop a test at any time by issuing a new diagnostic configuration to disable it. If
the online diagnostics test fails on the active card, a switchover is triggered and the active card
becomes the standby, and an error message comes on declaring the standby card as failed.
Note Online diagnostics do not detect operational errors.
• Off-line diagnostics ensure the standby card is ready to be switched over to. Offline diagnostics tests
are performed only on the standby card. Areas for diagnosis include hardware components and cell
paths. Off-line diagnostics are destructive. Intensive tests are performed on a card including memory
tests and registers read/write tests. It temporarily puts a standby card out of service and makes it
unavailable to be switched over to in case of active card failure. When tests are done, the card is reset
to its normal state. If the active card fails while the standby card is running off-line diagnostics,
off-line diagnostics are immediately aborted
Note Off-line diagnostics will not be performed on cards with APS configured.
The MGX 8850 and MGX 8950 switches run offline diagnostics in the following areas:
• Processor subsystem: NVRAM and BRAM
• ASIC tests: Atlas (register test, ingress memory, egress memory) and framer (register test)
• UI S3 back card: UIS3 BC register test
Both control path and data path must to be tested in order to have a complete test coverage on the entire
connection path within a card. The control path is the path that carries IPC messages between cards. The
diagnostic data path is the path for cells travelling between the backplane and the loop back device.
Configuring Offline and Online Diagnostics Tests on the AXSME Card
At the active PXM45, enter the cnfdiag command as follows to enable online diagnostics tests on the
appropriate card:
cnfdiag <slot> <onEnb> <offEnb> [<offCover> <offStart> <offDow>]
Note Diagnostics commands are run from the PXM45, regardless of whether they are testing the PXM or the
AXSM
Table 7-47 tells you how to set these parameters to run online diagnostics tests.