Cisco 3800 Series - Manual (Page 26)

LED Indicators
12
Overview of Cisco 3800 Series Routers
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LED Indicators
LEDs can help you monitor your router’s performance and operation by providing power, activity, and
status information. For an explanation of LED activity during power-up, see the
“Verifying LED
Indications” section on page 34 of “ Powering Up Cisco 3800 Series Routers .” To use LEDs for
troubleshooting, see Table 1 in “ Troubleshooting Cisco 3800 Series Routers .”
For descriptions of LEDs on network modules or interface cards, see the Cisco Network Modules
Hardware Installation Guide and the Cisco Interface Cards Installation Guide .
Ventilation
Three internal multispeed fans cool the routers, controlled by a temperature sensor. At ambient
temperatures below 40 degrees C, they operate at low speed to conserve power and reduce noise. At
40 degrees C or above they operate at high speed. The power supply has its own integrated fan.
Note On the Cisco 3825 router, when the router is installed with a Inline Power (ILP) power supply, the
internal multispeed fans will operate at high speed only. To verify the fan speed, use the show
environment command.
Real-Time Clock and Battery
An internal real-time clock (RTC) with battery backup allows the routers to check the validity of the
certification authority (CA) certificate. The RTC is accurate under the operating environmental
conditions specified for the router.
The clock and battery are permanently installed. Under the specified operating environmental
conditions, the battery lasts the life of the router and does not need to be replaced.
Technical Specifications
Table 2 and Table 3 list Cisco 3800 series system specifications.
Table 2 Cisco 3825 Router Specifications
Specification Value
Dimensions (H x W x D) 3.5 x 17.1 x 14.7 in. (8.9 x 43.4 x 37.3 cm)
2 rack unit height
Weight (minimum) 23 lb (10.5 kg)