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Cisco 1120 Connected Grid Router Hardware Installation Guide
OL-26438-02
Chapter 6 Making Network Connections
Additional Router Connections
Figure 6-5
USB Port (Item 1)
Connecting the Alarm Port
About
The alarm port provides data about fatal or severe errors that can cause the system software to crash.
The alarm port is connected to a normally closed solid state relay. Cisco CG-OS writes to a hardware
port and the relay contact opens. If the system enters into a ROM monitor (ROMmon) or watchdog reset
state, the relay contacts close. The closing contacts alert the alarm annunciator or monitor that a
Cisco CG-OS crash has occurred.
If interfaces fail or other non-fatal errors occur, the alarm port does not respond. Continue to use SNMP
to manage these types of errors.
Connecting
•
You can connect this port while the router is operating normally.
•
If you use an alarm system on your network, connect the alarm port to an alarm system with an alarm
cable that you provide.
Related Information
Router Hardware Description
includes detailed information about this port, including:
•
Alarm input and output
•
Location on the router
•
Link to pinout information
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