3750 boot from TFTP

I was wondering, when you set up the the boot varibable on a 3750 switch you have the option of setting TFTP as the source for the IOS file.

However in rommon there is no way to set up the TFTP varibables?

Can a 3750 be booted from a TFTP server, and if so is it possible to set this up from the ROMMON? I was just wondering as if you have a switch with a broken IOS, can you set it to boot from TFTP?

DevilWAH

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peanutnoggin

DevilWAH,

I've never tried it on a 3750, I've only had to do it on a router... but the procedures should be identical. Checkout this link for more detail. HTH.

-Peanut

VAHokie56

You can always upload a new IOS threw the console cable...just don't forget to up the baud rate

DevilWAH

VAHokie56 wrote: »

You can always upload a new IOS threw the console cable...just don't forget to up the baud rate

yer i know that, but with a router you can use TFTP from ROMMON and on a switch you can set it to boot from TFTP so it seems like ROMMON must support TFTP in some way

tiersten

Cisco fixed configuration switches don't have a ROMMON capable of doing TFTP and the 3750 doesn't appear to have a boot helper capable of doing it either. XMODEM is all you've got for a 3750. No idea why Cisco don't make it capable of doing TFTP from ROMMON. There must be some sort of technical limitation.

I know that this isn't possible because I've had the misfortune of having to load in IOS on a 3750 stack...

mikearama

tiersten wrote: »

Cisco fixed configuration switches don't have a ROMMON capable of doing TFTP and the 3750 doesn't appear to have a boot helper capable of doing it either. XMODEM is all you've got for a 3750.

I read through the thread wondering if anyone was going to make this statement... and there you have it. Nicely done tiersten.

I also don't know why tftp isn't an option in the 3750, but it isn't. Pity. However, upping your baud to 115200 makes the xmodem process at least tolerable.

DevilWAH

I relise that there is no TFTP support in rommon to copy over an IOS, I have had to recove a few through Xmodem.

But with in the ios you can set some thing like.

#boot system tftp:\ip.address\file name

sugesting you can boot the switch from a tftp server ( i have never actuly tried this to see if it really works)

that suggests that the ROMMON does support tftp to some degree, or at least a switches boot helper before it boots to an IOS supports tftp.

So what I was wondering is not can you copy the IOS from rommon mode. But if you can set a switch to boot to tftp when it is already running an ios, assuming it works can you not make this setting also from rommon?

I supose what I should do is get a 3750 and see if it can indeed boot from a TFTP server at some point

tiersten

DevilWAH wrote: »

that suggests that the ROMMON does support tftp to some degree, or at least a switches boot helper before it boots to an IOS supports tftp.

It doesn't work.

DevilWAH

tiersten wrote: »

It doesn't work.

Ah ha

see I love it when you can configure something on cisco but it does not actuly work

cheers

tiersten

DevilWAH wrote: »

Ah ha see I love it when you can configure something on cisco but it does not actuly work

I believe you can do something like chain loading so your flash IOS then loads IOS from somewhere else but you need a working IOS in the first place to do that. This is from vague memories and not something I actually use so this feature may not actually exist

notgoing2fail

Devil,

Where did this question come from? Do you have access to a 3750?

As for Cisco letting you configure things that don't work. Don't even start. I fully configured an L3 switch to be a VPN endpoint with no errors. But VPN won't work....

DevilWAH

notgoing2fail wrote: »

Devil,

Where did this question come from? Do you have access to a 3750?

As for Cisco letting you configure things that don't work. Don't even start. I fully configured an L3 switch to be a VPN endpoint with no errors. But VPN won't work....

5 years designing and configuring a few hundred of the things

yer a bit of practice with them

Had 3 of them in my test network there.

Now had to leave them behind, but still work on them in my new job a lot running IOS upgrades.

Mind you I still have one sitting under my desk to play with at the new job that I have been training some guys on. Showing them how to recover from failed upgraded and broken IOS images.

I know on routers I use TFTP to copy over in ROMMON, and like I say I have seen the boot system tftp

xx.xxx.xxx.xxx/ios.bin on a 3750. So I was just curious, as like the people who have posted I did not think it was possible and had never seen the settings in ROMMON. But just wanted to confirm I was not missing something.

But now I have much better things than 3750's to play with, got 8 racks full of cisco equipment to use for lab/study

notgoing2fail

DevilWAH wrote: »

5 years designing and configuring a few hundred of the things yer a bit of practice with them Had 3 of them in my test network there.

Now had to leave them behind, but still work on them in my new job a lot running IOS upgrades.

Mind you I still have one sitting under my desk to play with at the new job that I have been training some guys on. Showing them how to recover from failed upgraded and broken IOS images.

I know on routers I use TFTP to copy over in ROMMON, and like I say I have seen the boot system tftpxx.xxx.xxx.xxx/ios.bin on a 3750. So I was just curious, as like the people who have posted I did not think it was possible and had never seen the settings in ROMMON. But just wanted to confirm I was not missing something.

But now I have much better things than 3750's to play with, got 8 racks full of cisco equipment to use for lab/study

Understood. I will be getting my hands on some 3750's this week to play with. Will cable them up with the stack cables for production. Not everyone is lucky enough to have some just "laying" around under their desk...

So what do you have in this rack I'm curious....

DevilWAH

notgoing2fail wrote: »

Understood. I will be getting my hands on some 3750's this week to play with. Will cable them up with the stack cables for production. Not everyone is lucky enough to have some just "laying" around under their desk...

So what do you have in this rack I'm curious....

look under the ccna lab pic thread for the list