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New Member

Loading IOS image from TFTP server

I am trying to boot off of a tftp server and having no luck.....

my config as follows:

sing 780 out of 30712 bytes


version 12.0

service timestamps debug uptime

service timestamps log uptime

no service password-encryption


hostname c3620


boot system tftp c3620-ik2os-mz.120-4.T

boot system flash c3620-i-mz.120-23

boot system rom

enable secret 5 $1$UigF$8mIEFq1C329WB.aWCfyX5/

enable password cisco


ip subnet-zero




interface Ethernet0/0

ip address

no ip directed-broadcast

I am able to copy the image to the flash with no problem. This tells me there is no connection problem with the tftp server.

any idea????

thanks in advance

  • Other Network Infrastructure Subjects
New Member

Re: Loading IOS image from TFTP server

does the file name have a ".bin" behind it? if yes, you should type it into the

boot system tftp c3620-ik2os-mz.120-4.T.bin

boot system flash c3620-i-mz.120-23.bin



New Member

Re: Loading IOS image from TFTP server

no the file doen't have ".bin" behind it. Is the any particular config-register setting, other than the 0x2102, I need to set to in order to have the router look for the tftp server at boot up??


Re: Loading IOS image from TFTP server

try putting an ip helper address with the address of your tftp server on the interface that provides the route to the tftp server

New Member

Re: Loading IOS image from TFTP server

Is the file in the root directory of the tftp server. If not you will need to add the path in front of the filename.

i.e boot system tftp cisco/ios/c3620-ik2os-mz.120-4.T

Cisco Employee

Re: Loading IOS image from TFTP server

What's the first file you have in your flash ?

When netbooting (booting from a tftp server) a router will:

1) boot his bootimage

2) read the config

3) bring the interfaces up

4) download the image given in the first boot system found in the config

With the 36xx there's no bootimage, but in order to netboot it needs to be able to read the config and bring the interfaces up. So it'll try to boot the first file found in flash.

From that point different thing could happen:

1) no bootable flash in flash

2) first file is not bootable

3) memory used by the IOS from flash is so big that it cannot download the tftp image

4) ...

A boot sequence log should show were things go wrong.