How to load IOS image via TFTP in Rommon.
Have you ever been in pain when you’re stuck with a router that has no image or the image on router is corrupt? We have experienced the looping boot and result in corrupted IOS. After getting the IOS, we still need to think about how to load the IOS image. Using the serial port for uploading the images will take you ages and we don’t recommend that.
For the information, you can use TFTP from ROMMON to upload your IOS image. Most of routers seem to have a TFTP client built in. With this feature, you don’t have to wait ages to upload your images. You just need a TFTP server installed on your notebook or PC. There are many free TFTP servers on internet that you can choose.
Here are the basic steps to load the images via TFTP on ROMMON:
rommon 1>
IP_ADDRESS=192.168.4.1
IP_SUBNET_MASK=255.255.255.0
DEFAULT_GATEWAY=192.168.4.254
TFTP_SERVER=192.168.4.2
TFTP_FILE=c2801-adventerprisek9-mz.124-15.T.bin
tftpdnld
The IP Address, and other variables depend on your environment. After executing command tftpdnld , below is the result:
IP_ADDRESS: 192.168.4.1
IP_SUBNET_MASK: 255.255.255.0
DEFAULT_GATEWAY: 192.168.4.254
TFTP_SERVER: 192.168.4.2
TFTP_FILE: c2801-adventerprisek9-mz.124-15.T.bin
TFTP_MACADDR: 00:25:84:a4:18:1e
TFTP_VERBOSE: Progress
TFTP_RETRY_COUNT: 18
TFTP_TIMEOUT: 7200
TFTP_CHECKSUM: Yes
FE_PORT: 0
FE_SPEED_MODE: Auto Detect
.
Invoke this command for disaster recovery only.
WARNING: all existing data in all partitions on flash will
be lost!
Do you wish to continue? y/n: [n]: y
…
Receiving c2801-ipbasek9-mz.124-9.T7.bin from 192.168.4.2 !!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
….
File reception completed.
Validating checksum.
Copying file c2801-ipbasek9-mz.124-9.T7.bin to flash.
program load complete, entry point: 0x8000f000, size: 0xc100
.
Initializing ATA monitor library…….
.
Format: Drive communication & 1st Sector Write OK…
Writing Monlib sectors.
……………………………………………………………………..
………………
Monlib write complete
Format: All system sectors written. OK…
Format: Operation completed successfully.
Format of flash: complete
program load complete, entry point: 0x8000f000, size: 0xc100
Initializing ATA monitor library…….
rommon 7 >
After above progress, all you have to do is execute “reset” command .
PS: If you need to boot IOS image via tftp server (not from Flash), you can type “tftpdnld -r”
