Cisco 1721 - Manual (Page 70)

Appendix C Installing and Upgrading Memory and Virtual Private Network Modules
Opening the Chassis
C-2
Cisco 1721 Router Hardware Installation Guide
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Warning Before working on a system that has an on/off switch, turn OFF the power
and unplug the power cord.
Warning Do not work on the system or connect or disconnect cables during periods
of lightning activity.
Warning Read the installation instructions before you connect the system to its power
source.
Warning Before working on equipment that is connected to power lines, remove
jewelry (including rings, necklaces, and watches). Metal objects will heat
up when connected to power and ground and can cause serious burns or
weld the metal object to the terminals.
Warning Hazardous network voltages are present in WAN ports regardless of
whether power to the router is OFF or ON. To avoid electric shock, use
caution when working near WAN ports. When detaching cables, detach the
end away from the router first.
Opening the Chassis
In order to upgrade Cisco 1721 router memory, you must open the chassis.
Opening the chassis requires a number one Phillips screwdriver.
Follow these steps to open the chassis:
Step 1 Make sure the router is turned off and is disconnected from the power supply.
Step 2 Turn the router upside down, and rest the top of the router on a flat surface.
Step 3 Use the Phillips screwdriver to remove the four screws that hold the top and
bottom of the chassis together, as shown in
Figure C-1 .