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Cisco 1900 Series Hardware Installation
OL-19084-02
Chapter 1 Overview of the Router
Hardware Features
Chassis Ventilation
An internal 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. See the
“Chassis Airflow Diagram” section on page 4-3.
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 the certification authority (CA) certificate. The
Cisco
1900 series router has a lithium battery. This battery lasts the life of the router under the operating
environmental conditions specified for the router, and is not field-replaceable.
CF 0 Green Flash memory is busy.
Note Do not remove the CompactFlash memory card
when this light is on.
Next to the
CF0 slot
Amber Initialized with error.
Blinking
Green
then
turns off
CompactFlash is ready for removal.
Note Remove the CompactFlash when the light turns off.
S (Speed) 1 blink +
pause
GE port operating at 10 Mb/s. Rear panel
2 blink +
pause
GE port operating at 100 Mb/s.
3 blink +
pause
GE port operating at 1000 Mb/s.
L (Link) Green GE link is established. Rear panel
Off No GE link is established.
EN (RJ-45
console port)
Green The RJ-45 console port is active. Rear panel,
next to the
console
port
EN (USB serial
console port)
Green The USB console port is active. Rear panel,
next to the
USB
console
port
1. SSID = Service Set Identifier.
2. eUSB = embedded USB
Table 1-4 Summary of Cisco 1900 Series LED Indicators (continued)
LED Color Description Location