Equipment Support > Hardware By Brand > Cisco > 1841 routers without flash memory

1841 routers without flash memory

CF should be 64MB or less. Some have experience with larger CFs... anywho, format it in windows, and place the bin file on it. pop it in and turn the router on... you can boot the router from tftp and format it as well if you choose to do so the painful way.

reply to Sydn
If you have USB thumb drive, you can use it to transfer IOS to router's flash. Simply copy suitable IOS image from your PC to the USB drive, plug in the USB drive to the router, and copy down the image.

I don't prefer to format Compact Flash on PC because there might be a potential issue of incompatibility between PC and router. I would rather format the Compact Flash on the router to make sure compatibility is in place.

Of course you can always do what a lot of people do which is downloading IOS image from TFTP server on ROMMON mode using tftpdnld command. With any case, make sure you format the Compact Flash first and verify that the Compact Flash storage size is large enough to keep the image.

reply to Sydn
My personal favorite method is take any USB memory card reader, insert said CF card in
and copy over the IOS, keys, etc via Windows. Problem solved.

Regards

The problem here is that the router may not be able to read that specific model/size CF card. Also, Cisco is well known for requiring "flash" to be formated in the device. (it puts a device driver on the device.)

As others have said, the easiest path is to boot from usb, format the CF, and copy from usb to CF. It's fast, simple, and you're certain it likes the CF card.

reply to Sydn
thanks for the replies , im still waiting for the new CF cards so i can try the methods that you guys mentioned and i will let you know which is the best !

reply to aryoba
@ aryoba , why do i need to format the card ? it's brand new ?

Especially brand-new Compact Flash, you need to format it on the router to ensure read/write compatibility as described on earlier posts.

but im in the ROMMON mode how can i format it ? there is no such command such as format ? help

When the router is on ROMMON mode, here is what you can do

Step 1:

* Type in confreg 0x2142 and reset to make sure the boot process you are about to do in order to activate the IOS image the router is going to use is starting fresh, bypassing any possible saved/prior configuration

Step 2:

Choose one of the following choices

Choice #1

* Prepare a USB Flash drive
* Download suitable IOS image from your PC to the USB Flash drive
* Stick the USB Flash drive to the router USB port
* On the ROMMON prompt, use boot command to boot the router using the IOS image stored in the USB Flash drive. You can use dev and dir commands to get the USB Flash drive code and to get the IOS image name when you need to specify those during the boot command usage. You can also use ? at any time on ROMMON mode to help you using any ROMMON mode commands

Example:
rommon 1>boot usbflash0:[ENTER THE IOS IMAGE NAME HERE]

* Once the router is up normally, you can simply use the copy command to format and copy IOS image from USB Flash drive to Compact Flash

Choice #2

* Prepare TFTP server
* Store suitable IOS image in one of the TFTP server directory (or folder if you use Windows machine)
* On the ROMMON prompt, use tftpdnld command to format and copy the IOS image from the TFTP server to the Compact Flash
* Boot the router using the IOS image in the Compact Flash using boot ROMMON command

Example:
rommon 1>boot flash:[ENTER THE IOS IMAGE NAME HERE]

Step 3:

* Once the router is up normally, set the configuration registration value back to default which is 0x2102 by doing the following

config-register 0x2102
write memory (or copy running-config startup-config)
reload

Should you decide to use Choice #2 (using tftpdnld command), then you need to setup the following values in ROMMON before using the command.

Step 1:
You need to enter the following
* Router IP address
* Router IP subnet mask
* Router default gateway
* TFTP server IP address
* IOS image file name

You enter those info by typing the following on ROMMON prompt.

IP_ADDRESS={The IP address for the router}
IP_SUBNET_MASK={The subnet mask for the router}
DEFAULT_GATEWAY={The default gateway for the router}
TFTP_SERVER={The IP address of the server to fetch the image from}

Step 2:
After all above settings are correct, enter this command as well:

TFTP_FILE={The proper image FULL name including directories and sub-directories when applicable}

Step 3:
Type tftpdnld {press ENTER}

reply to cramer
I must've been one of the lucky few then cramer, got a bunch of used CF cards for
some 1811s. Loaded the IOS, popped em in and they just ran. Wierd.

Regards

reply to aryoba
Choice 1:

using the USB, the problem is that the router does not recognize the USB ? its 2g size and i formatted it as FAT but it does not show up ??

You may need an upgraded ROMMON - C1841_RM2.srec.124-13r.T 'adds boot from usb flash drive capability'.

when i reset it says

"
rommon 3 > reset

System Bootstrap, Version 12.3(8r)T8, RELEASE SOFTWARE (fc1)

"
if i need to upgrade then how?

thanks mate

Unfortunately, the dilemma is that, as far as I know (and I'm open to correction on this!), you can only upgrade ROMMON from within IOS and not from ROMMON itself.

»www.cisco.com/en/US/docs/routers···#wp51176

if that is the case then i have to go with choice two which is using the TFTP server !! but that's insane USB needs upgraded bootstrap and bootstarp needs a running IOS but you dont have a running IOS so NO USB lol..

i will do some research on that

reply to Sydn

rommon 8 > boot usbflash0: c1841-advipservicesk9-mz.150-1.M.bin
boot: cannot open "flash:"
an alternate boot helper program is not specified
(monitor variable "BOOTLDR" is not set)
and unable to determine first file in bootflash
boot: cannot open "usbflash0:"
boot: cannot determine first executable file name on device "usbflash0:"
rommon 9 > dev
Devices in device table:
id name
flash: external compact flash
bootflash: boot flash
eprom: eprom
rommon 10 >

no space after the usbflash0:

Also, I believe the largest file partition recognized from my experience is 256MB USB drives...