Probably a stupid question (2501's)

Hi,

Hoping you can help. Im gradually working my way through all things CCNA, tonights topic was upgrade the IOS. Seemed easy enough, i put 16mb of flash memory in before i started as there was only 4mb in there.

The .bin file copied accross no problem, its now running 12.0 however i dont understand why it now shows the flash memory as 16mb [read only]. I was going to erase the flash and copy across again just to make sure i remember the process but now just get an error message saying flash memory is read only and cannot be erased???

Have i missed a command to make the RAM read/write as it was showing at first boot?

Thanks for your help

Paul

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zom

r u trying to say that u can't erase the ios as u wanna reinstall the ios? my router too showing the read only command....i never really tried to flash my ios b4 as i am also still learning any 1 pls help? thx alot ^^

2lazybutsmart

2500 series run from flash memory so you can't erase flash while the router is running. If you want to copy an image to flash, you have to use RxBoot.

http://www.cisco.com/en/US/products/hw/routers/ps233/products_tech_note09186a00800941aa.shtml

2lbs.

paule999

Cheers lazybutsmart!

I'll give this a go tonight, someone suggested that it was because i was only running 8mb DRAM. They also suggested that i wouldnt be able to run any IOS 12 on a 2500... Not so sure thats right

2lazybutsmart

my 2520s run 12.3

rossonieri#1

paule999 wrote:

Cheers lazybutsmart!

I'll give this a go tonight, someone suggested that it was because i was only running 8mb DRAM. They also suggested that i wouldnt be able to run any IOS 12 on a 2500... Not so sure thats right

rule no 1 -> be careful when upgrading IOS - make mistakes and the router wont boot if you erased the flash totally.

rule no 2 -> read the IOS requirement before upgrading such as flash capacity etc.

and,
IOS 12.0(7) will do OK on 2500.

have you set your TFTP server?

cheers.

paule999

Thanks guys really appreciate the advice.

Have run out of time to check tonight now (been revising 150 pages of course notes for tomorrows exam) but the link from earlier looks promising.

Im using my laptop as the tftp server, running solar winds tftp server only because it was a free download. When i transferred the ios i got the message i was expecting asking if i would like the flash ram erased. The router still boots up ok and i can configure interfaces etc just confused as to why the flash now shows read only.

So tomorrows quest is switch the 8mb dram for 16mb and follow the instructions in the link to reload the ios through rxboot.

I guess at least by buying crappy routers you get more problems to test you while you learn

Thanks

Paul

rossonieri#1

"When i transferred the ios i got the message i was expecting asking if i would like the flash ram erased. The router still boots up ok and i can configure interfaces etc just confused as to why the flash now shows read only. "

that is because your 2500 router only have 8mb of flash -
if you like to change to your new IOS you have to delete the old file.

DRAM only used as router processing temporary media.