Flash memory upgrade question

Hello TechExams,

I just recently purchased a few Cisco 1841 routers. They have all of the default specs in them. I found out that the IOS that I would like to upgrade them to requires an increase in flash memory. My question is, does a brand new flash memory stick some with some sort of base IOS image that will allow me to stick it in and go through the IOS upgrade process? I just don't see how I would be able to put an IOS image on the new flash card if there isen't even a base image on it that the router can boot from. I've honestly googled this for awhile but I really don't find anything that helps me.

Sorry for the nooby question, the CCNA exams really don't cover this.

Thanks in advanced,
-Joe

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Comments

bbarrick

Can you not boot to IOS via tftp?

JoeBirds

bbarrick wrote: »

Can you not boot to IOS via tftp?

I may be thinking to hard about this, so please feel free to vritually smack me, but how would your router even boot up if there is litterally nothing on the flash stick? I wouldn't even be able to get to a command prompt to access a TFTP server, am I right?

bbarrick

JoeBirds wrote: »

I may be thinking to hard about this, so please feel free to vritually smack me, but how would your router even boot up if there is litterally nothing on the flash stick? I wouldn't even be able to get to a command prompt to access a TFTP server, am I right?

As always, I'm new at this so don't take my word for it. I was just researching how to upgrade IOS myself and ran into rommon, which is ROM Monitor I believe? You can change the boot procedure to check tftp for an IOS image. I've never done it, so don't quote me on it but maybe that will help you find what your looking for via google.

jahsoul

Like bbarrick said, if it doesn't have nothing to boot from, the router will automatically boot into rommon, and from there, you can run tftpdnld. Either that or have a router with a secondary compact flash slot, and then just tftp the image to that card and then place that card in your router.

theodoxa

With Compact Flash, you have two choices:

1) Install IOS via TFTP from ROMMON

ROMMON 1>IP_ADDRESS=192.168.0.5
ROMMON 2>IP_SUBNET_MASK=255.255.255.0
ROMMON 3>DEFAULT_GATEWAY=192.168.0.1
ROMMON 4>TFTP_SERVER=192.168.0.10
ROMMON 5>TFTP_FILE=c1841-advipservicesk9-mz.151-2.T.bin
ROMMON 6>tftpdnld

Substitute the values (Available IP Address on your home network, Subnet mask, Default Gateway, IP Address of your TFTP Server, and Filename of the IOS Image you want to download) for your network.

Connect Fa0/0 on your router to your home network
Install and configure a TFTP Server on one of your computers
Place the IOS image in the directory you chose when installing the TFTP server
Run the commands listed above, substituting the correct IP Addresses, Subnet Masks, and Filenames

2) The much easier way. If the Compact Flash card has already been formatted [on a Cisco router] or has been previously used in a Cisco Router, you can simply take it to any computer with a Compact Flash reader, insert the card in the computer and just drag and drop the IOS image onto the card. If its the first IOS image on the card, the router should boot right into it. If there is already an IOS image on the card [which doesn't seem to be the case,] the router will likely continue to use that image until you specify which IOS to use using the boot system command in IOS.

gregorio323

Before you upgrade the IOS image please make sure you have sufficient memory to run the Image.

JoeBirds wrote: »

Hello TechExams,

I just recently purchased a few Cisco 1841 routers. They have all of the default specs in them. I found out that the IOS that I would like to upgrade them to requires an increase in flash memory. My question is, does a brand new flash memory stick some with some sort of base IOS image that will allow me to stick it in and go through the IOS upgrade process? I just don't see how I would be able to put an IOS image on the new flash card if there isen't even a base image on it that the router can boot from. I've honestly googled this for awhile but I really don't find anything that helps me.

Sorry for the nooby question, the CCNA exams really don't cover this.

Thanks in advanced,
-Joe

DCD

JoeBirds wrote: »

Hello TechExams,

Sorry for the nooby question, the CCNA exams really don't cover this.

-Joe

It's cover by the CCNA material CCNA - Cisco Router Boot Sequence - YouTube