Note This publication is for the router installer, who should be familiar with electronic circuitry
and wiring practices and have experience as an electronic or electromechanical technician.
When you upgrade Flash memory, a Trivial File Transfer Protocol (TFTP) file server must be
available that has the desired Cisco Internetwork Operating System (Cisco IOS) software
image—Release 10.2(6) or later. These Cisco IOS files can then be downloaded into the upgraded
Flash memory using TFTP. Consult your network administrator about the availability of TFTP file
servers and Cisco IOS software on your network. The router will not be fully functional without the
system software and running configuration. Consult the appropriate Cisco IOS software publication,
which is available on the Cisco Connection Documentation Enterprise Series CD or as a printed
document, for TFTP procedures.
Note One upgraded router can serve as a TFTP server to upgrade other routers.
Figure 1 shows the front view of a Cisco 4000 series router.
Figure 1 Front View of a Cisco 4000 Series Router
Memory Systems
The Cisco 4500, Cisco 4500-M, Cisco 4700, and Cisco 4700-M memory systems (see Figure 2)
have the following functions:
• Main memory—Stores the running configuration and routing tables. The Cisco IOS software
executes from main memory.
• Shared memory—Used for packet buffering by the router’s network interfaces.
• NVRAM—Stores the system configuration file and the virtual configuration register.
• Flash memory—Stores the operating system software image and the boot helper software. The
boot helper image allows you to boot the router when Flash memory does not contain a valid
system image.
To Next Page
Loading...
Need help?
General
