Cisco Systems CISCO1841-HSEC/K9-RF manual Chassis Ventilation, Real-Time Clock

Chapter 2 Overview of Cisco 1800 Series Routers (Modular)

Hardware Features

Table 2-5	Summary of Cisco 1800 Series LED Indicators (continued)
LED		Color	Description	Location:
100 (FE 0/1)		Green	On indicates a 100-Mbps link. Off indicates a 10-Mbps link.	Back
Link (FE 0/1)		Green	On when the router is correctly connected to a local Ethernet	Back
			LAN through Ethernet port 1.
AIM		Green	On indicates presence of an AIM in the internal AIM slot.	Back

Figure 2-5summarizes the LED indicators for the Cisco 1861 ISR that are located in the router bezel.

Figure 2-5 LEDs on the Front Panel of the Cisco 1861 Integrated Services Router

SYS POE VM WLAN

1

4

3

2

1

230870

1	SYS	Solid green	Online
2	POE	Solid green	Connected
3	VM	Solid green	Online
4	WLAN	Blinking green	Connected

Chassis Ventilation

An internal three-speed fan provides chassis cooling. An onboard temperature sensor controls the fan speed. The fan is always on when power is applied to the router. Under most conditions, the fan operates at the slowest speed to conserve power and reduce fan noise. It operates at the higher speeds when necessary under conditions of higher ambient temperature.

Real-Time Clock

An internal real-time clock with battery backup provides the system software with time of day on system power up. This allows the system to verify the validity of a certification authority (CA) certificate. The backup battery is a socketed lithium battery. This battery lasts the life of the router under the operating environmental conditions specified for the router, and is not field replaceable.

Cisco 1800 Series Routers (Modular) Hardware Installation Guide

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