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Cisco 2900 Series and 3900 Series Hardware Installation Guide
OL-18712-02
Chapter 1 Overview of the Routers
Hardware Features
• Figure 1-19 shows Cisco 2901 airflow.
• Figure 1-20 shows Cisco 2911 airflow.
• Figure 1-21 shows Cisco 2921 and 2951 airflow.
• Figure 1-22 shows the Cisco 3900 series standard (non NEBS) airflow configuration. For NEBS, the
airflow is reversed.
• Figure 1-23 shows the Cisco 3900 series standard NEBS airflow configuration.
Figure 1-19 Cisco 2901 Router Airflow
Figure 1-20 Cisco 2911 Router Airflow
Figure 1-21 Cisco 2921 and Cisco 2951 Router Airflow
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SYS ACT POE
Cisco 2900 Series
SYS ACT
SYS
PWR1
AUX
PWR1
SYS
PWR2
AUX
PWR2
Cisco 2900 Series
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