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Cisco routers have always had a steep learning curve for performing
even the most basic administrative tasks, like firmware updates and
configuration backups. Now, with commodity CF (compact flash) memory and USB
memory sticks, you can handle these tasks quickly and easily.

In the old days, the usual method of upgrading Cisco routers
required you to have access to a TFTP or FTP server and you had to have basic
network configuration before you could begin to download firmware or configuration
files. Even when everything was ready to roll, downloading tens of megabytes of
firmware binaries took a couple of minutes or more depending on the speed of
the connection to the TFTP server and the size of the firmware. In cases where
the TFTP server was located across the Internet or WAN with limited T1-class
bandwidth, it could take hours to download a new firmware. FTP servers were a
little better because they could deliver the firmware at near wire speeds, but
even that took tens of minutes.

Now, with the newer
Cisco 1800,
and 3800
series routers, which use commodity CF memory cards that can be loaded into any
media adapter, you can do firmware updates in seconds using drag-and-drop.
Cisco designed its newest routers to read the FAT file system instead of its
primitive proprietary drive format, which couldn’t even recover deleted file
space unless you ran the time-consuming “squeeze” command. By going
with FAT, you can literally stick the CF card in your computer’s CF slot (~$9
for a USB 2.0 compact
flash adapter
, if you don’t have one), delete the old firmware, and
drag the newest firmware onto the CF card. If your computer has a USB 2.0
adapter, you can expect 20 MB firmware to copy in seconds, whereas it would
have taken 10-100 minutes with a TFTP server, depending on connection speed.
Even USB 1.1 solutions are preferable to the TFTP or FTP servers.

As a bonus, you can also copy a startup configuration file
onto the CF card. Note that while Cisco routers load their firmware from the CF
card, router configuration is loaded from NVRAM (nonvolatile RAM), so the
router configuration can’t be directly booted from the CF card. But you can copy
the configuration file from the CF card to NVRAM to recover a configuration
file or do it in the reverse direction to back up a configuration.

Once the configuration file is on the CF card and the router
boots up with the CF card inserted, you just need to issue this file copy

Copy flash:startup-config nvram:startup-config

This assumes you named the configuration file “startup-config”
before you dragged it from your computer to the CF card and that the router is
in “enable” mode. This command takes the startup configuration on the
CF card and transfers it to the nonvolatile RAM of the router, so that it will
boot with it the next time your start or restart the router. If you need to
back up a good configuration of a router to a CF card, you simply reverse the
arguments in the copy command and type:

Copy nvram:startup-config flash:startup-config

This is especially useful if you ever need to replace a
defective router and Cisco sends you a new one, which usually comes with the
base firmware and no configuration. To convert a factory-fresh router into full
production, you simply put the old CF card into the new router and boot it up.
Once it has booted with the default configuration and the proper firmware,
issue the first copy command listed above and reboot the router. When the
router finishes booting, it will be completely operational. This entire process
could easily have taken an hour or more if you had to manually copy everything
via TFTP or FTP.

In addition to CF card support, the newest Cisco routers with IOS 12.4 or better will even read USB memory sticks. This enables you to upgrade, back up, or recover your firmware and configuration to an additional removable device. Operationally, it’s the same as the CF card, only you refer to it
as “usbflash:” instead of “flash:”.

The one downside to USB adapters is that you can’t boot off
them. Unlike CF cards, they aren’t recognized in Cisco RMON mode. Only a booted
router running IOS 12.4 or better can read or write to USB adapters. The plus
side to USB adapters is that you can use them as a removable backup medium,
whereas the CF card isn’t removable since the router can’t boot without it.

And finally, this new line of Cisco routers offers
significant price benefits. You no longer have to pay hundreds of dollars for
Cisco-branded CF or USB flash memory because you can typically find 128 MB CF
and USB adapters for $15 or less. Although Cisco might lose a little revenue
because you can buy cheaper flash memory, it has made the network engineer’s
life much easier and gained a lot more customer loyalty.