From protocol perspective, please note that TFTP is completely different to FTP and the two are not interchangeable.
The variables you need to enter directly at the ROMMON prompt to download IOS image from TFTP server to the router as TFTP client are the following: In a situation where there is no established network, the router and the TFTP server should be in the same subnet and should share the same default gateway.
The router in this case is Cisco 1721 model which uses c1700 type IOS image file.
To match the above setting, here are ROMMON setting.
This FAQ assumes some knowledge from readers such as running basic IOS commands, setting up TFTP servers, some IP network understanding, and physical/hardware troubleshooting.
Following are typical cases in regards of router inability to boot up normally.
In issuing break sequence, you need to consider the following.
The break sequence to enter ROMMON mode varies, depending on your Terminal Emulator software you are using and Operating System your PC is running.
You as network administrator have option to specify the equipment to load specific image stored in specific media (either integrated flash memory chip, USB stick, Compact Flash card, or else).
This approach helps in case you want the equipment to load up file stored in PCMCIA/Compact Flash card as first preference instead of the one in the integrated flash memory chip.
For more troubleshooting info using tftpdnld command, please check out the following FAQ:»Cisco Forum FAQ »Corrupt image & router boots into rommon mode The key is to keep various router platforms that share the same flash memory chip hardware specification.
When you have two routers that share the same flash memory hardware specification, then you can always swap out flash memory between the two routers.
Either way, ensure there is basic connectivity between the router as TFTP client and the TFTP server that has no TFTP block or firewall in between. Let us say that the TFTP server setting are the following.