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Cisco routers have always had a steep learning curve for performingeven the most basic administrative tasks, like firmware updates andconfiguration backups. Now, with commodity CF (compact flash) memory and USBmemory sticks, you can handle these tasks quickly and easily.
In the old days, the usual method of upgrading Cisco routersrequired you to have access to a TFTP or FTP server and you had to have basicnetwork configuration before you could begin to download firmware or configurationfiles. Even when everything was ready to roll, downloading tens of megabytes offirmware binaries took a couple of minutes or more depending on the speed ofthe connection to the TFTP server and the size of the firmware. In cases wherethe TFTP server was located across the Internet or WAN with limited T1-classbandwidth, it could take hours to download a new firmware. FTP servers were alittle better because they could deliver the firmware at near wire speeds, buteven that took tens of minutes.
Now, with the newerCisco 1800,2800,and 3800series routers, which use commodity CF memory cards that can be loaded into anymedia 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 itsprimitive proprietary drive format, which couldn't even recover deleted filespace unless you ran the time-consuming "squeeze" command. By goingwith FAT, you can literally stick the CF card in your computer's CF slot (~$9for a USB 2.0 compactflash adapter, if you don't have one), delete the old firmware, anddrag the newest firmware onto the CF card. If your computer has a USB 2.0adapter, you can expect 20 MB firmware to copy in seconds, whereas it wouldhave 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 fileonto the CF card. Note that while Cisco routers load their firmware from the CFcard, router configuration is loaded from NVRAM (nonvolatile RAM), so therouter configuration can't be directly booted from the CF card. But you can copythe configuration file from the CF card to NVRAM to recover a configurationfile or do it in the reverse direction to back up a configuration.
Once the configuration file is on the CF card and the routerboots up with the CF card inserted, you just need to issue this file copycommand:
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 isin "enable" mode. This command takes the startup configuration on theCF card and transfers it to the nonvolatile RAM of the router, so that it willboot with it the next time your start or restart the router. If you need toback up a good configuration of a router to a CF card, you simply reverse thearguments in the copy command and type:
Copy nvram:startup-config flash:startup-config
This is especially useful if you ever need to replace adefective router and Cisco sends you a new one, which usually comes with thebase firmware and no configuration. To convert a factory-fresh router into fullproduction, 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 therouter finishes booting, it will be completely operational. This entire processcould easily have taken an hour or more if you had to manually copy everythingvia 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 itas "usbflash:" instead of "flash:".
The one downside to USB adapters is that you can't boot offthem. Unlike CF cards, they aren't recognized in Cisco RMON mode. Only a bootedrouter running IOS 12.4 or better can read or write to USB adapters. The plusside 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 offerssignificant price benefits. You no longer have to pay hundreds of dollars forCisco-branded CF or USB flash memory because you can typically find128 MB CFand USB adapters for $15 or less. Although Cisco might lose a little revenuebecause you can buy cheaper flash memory, it has made the network engineer'slife much easier and gained a lot more customer loyalty.