Upgrading the Memory in a Cisco 2500 Series Router

Picture of Upgrading the Memory in a Cisco 2500 Series Router
Wanna upgrade to that new IOS version to actually make your 2500 series Cisco router useful for something again but can't because you don't have enough RAM? I'll show you how to upgrade the RAM and where give you some advice on where to find some to upgrade to!
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Step 1: Find Your Replacement RAM

Picture of Find Your Replacement RAM
First off, you're going to need to find the RAM you'll be upgrading TO, keeping in mind that the Cisco 2500 Series has only one slot for RAM and does not support sticks bigger than 16MB.

Your two main options here are:
A) Purchase some probably overpriced Cisco RAM.
B) Find a really old computer than still uses the 72-pin SIMMs and rip a (non-EDO) stick of RAM out of it.

I chose the latter as I still have several computers old enough to be using this RAM strewn about and settled on this lovely 16MB stick of RAM. The thing to note here is that it is:
- 16MB or less
- Has 72 pins (split equally into halves)
- Is not EDO. I don't know how to tell this from looking at it, I just already knew it wasn't ;P

Step 2: Remove The Screws

Picture of Remove The Screws
You're going to need to start by removing the screws. There should only be one, or 3 if you have the rack mount brackets on it.

If you have the rack mount brackets, you need only remove the top screw(s), you can leave the bottom ones on.

Then, look at the bottom of the router near the back (side with the ports) and find the lone screw and remove it.
hypercube335 years ago
I just grabbed one of these beasts for $10, and hopefully find out that its 100% working tomorrow. If so, I'll run back after class and grab me another!
NuclearDog (author)  hypercube335 years ago
Heh, good plan. Picked up two (I think they're) 2521s off of E-Bay for $20 each almost a year ago. Shipping was a bugger, but I have been using one since as my main router. Instead of some cheap consumer crap, I have my old Cisco doing DHCP, NAT, etc. Awesomely reliable, cheap and a lot more fun :]
brianl7036 years ago
If you install two 8MB flash modules in a Cisco 2500 you can use a 16MB image. I don't think they ever made anything but 8MB flash modules for the Cisco 2500, so if both slots are populated, you have 16MB of flash. show flash will tell you how much flash you have and what's in it.
NuclearDog (author)  brianl7036 years ago
I tried installing two modules, but it would not treat them as a single file system, but as two seperate file systems, meaning I could not store a file greater than 8MB. Was there something I had to do to get it to treat it as a single filesystem?
You need to use the - partition flash 1 - command (I did it in ROM mode but I think you can use it in normal mode too) - Dan
Oooooooooooreos have nothing to do with this Instructable. Nice job!