Power Up Problems for Node and Cards
This section explains power up problems in a node or cards typically caused an improper power supply.
Problem
You are unable to power up a node or the cards in a node.
Possible Cause
Improper power supply.
Solution
Refer to the power information in the
document.
Network Level (Internode) Problems
The following network-level troubleshooting is discussed in this section:
• Fiber cut detection
• System restart after a fiber cut
• OCHNC circuit creation failure
System Restart after a Fiber Cut
When the network ALS setting is Auto Restart, the system automatically restarts after a fiber cut occurs.
MSTP system restart after a fiber cut is a fully automatic process regulated by a chronological sequence of
steps including the OSC link built-in amplifiers restart and amplifier power control (APC) regulation.
The successful completion of system restart is strictly related to possible changes of the insertion loss value
of the repaired span. A change in insertion loss is dependent on many factors, including the process of physically
repairing the fiber, a change in fiber length after repair, and so on.
Four different scenarios related to span loss are presented in this section:
1.
Span loss increased:
• Span loss change > 5 dBm
• OSC power value on the receiver < –42 dBm
2.
Span loss increased:
• Span loss change > 5 dBm
• OSC power value on the receiver > –42 dBm
3.
Span loss increased: 3 dBm < span loss change < 5 dBm
4.
Span loss increased: span loss change < 3 dBm
It is also possible that span loss decreased, but this is unlikely. This condition does not prevent the MSTP
system automatic restart process, but can lead (potentially) to issues downstream of the repaired span, for
example, a Power Overload condition on the OSC receiver or on the Trunk-RX port of a TXP or MXP card.
Note
These conditions are identified by specific alarms (see the
section in the chapter).
Cisco NCS 2000 series Troubleshooting Guide, Release 11.0
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General Troubleshooting
Power Up Problems for Node and Cards