User's Manual

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Cisco 1800 Series Routers (Modular) Hardware Installation Guide
OL-5876-03
Chapter 2 Overview of Cisco 1800 Series Routers (Modular)
Hardware Features
Figure 2-5 summarizes 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
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.
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
LAN through Ethernet port 1.
Back
AIM Green On indicates presence of an AIM in the internal AIM slot. Back
Table 2-5 Summary of Cisco 1800 Series LED Indicators (continued)
LED Color Description Location:
1 SYS Solid green Online
2 POE Solid green Connected
3 VM Solid green Online
4 WLAN Blinking green Connected
230870
1
SYS
POE
VM
WLAN
4
3
2
1