Question about 2500

Hi, I have a few questions about upgrading the memory in a 2500 router.

1. What is the significance of the memory numbers in the following output?

cisco 2516 (68030) processor (revision J) with 2048K/2048K bytes of memory.

It's obviously not a case of used/total as I have seen ones with the first number higer than the second.

2. The router currently has 8mb of system flash (read only).
To upgrade the flash memory, would I simply add another 8mb simm to the spare slot?
How is this actually going to help if the existing one is read only anyway?
Can data be spread across 2 flash simms?

3.To upgrade the main memory, could I simply purchase a single 16mb DRAM module, and bin the existing 2mb one?

Thanks for your help.

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Comments

routingbyrumor

Hi, I have a few questions about upgrading the memory in a 2500 router.

"1. What is the significance of the memory numbers in the following output?

cisco 2516 (68030) processor (revision J) with 2048K/2048K bytes of memory."

My assumption I think the 2048/2048 is 4096 which equals 4mb of ram "someone please correct me if I am wrong" To replace you would purchase a single 16mb stick on ebay or some other site and you would "bin" the 4mb stick.

It's obviously not a case of used/total as I have seen ones with the first number higer than the second.

2. The router currently has 8mb of system flash (read only).
To upgrade the flash memory, would I simply add another 8mb simm to the spare slot?
How is this actually going to help if the existing one is read only anyway?
Can data be spread across 2 flash simms? To make the flash writable to upgrade the IOS I would change the configuration register to 0x2101 and copy a new IOS into it. And yes if you had two sticks of 8mb each it would span and equate to one 16mb.

I would open to make sure you have a single SIMM of 8mb on one slot since there are two slots on the motherboard. That way you could verify that you have a single 8mb stick and not 2 4mb if thats possible. If you had a single stick you would purchase another 8mb and have 16mb of flash.

This is my assumption of what you could do since I had to do the same thing. I don't know how accurate I am if some would explain the 2048/2048 and if it equals 4mb or just a single stick of 2048.

EdTheLad

routingbyrumor wrote:

This is my assumption of what you could do since I had to do the same thing. I don't know how accurate I am if some would explain the 2048/2048 and if it equals 4mb or just a single stick of 2048.

As far as i can remember reading, this would be a 4mb stick.Its possible to logically partition the memory.In this case 2mb is used for nvram i.e. configs and stuff while the other 2mb is used for system operation.

TheShadow

True 2meg is always taken away as ed_the_lad mentioned so you have a 4meg stick. 2500's have one ram slot and two flash slots. Exception is that later build 2500's have 2meg on the main board so you can see wierd figures like 4096/2048 or 8192/2048 etc. Those later build units I believe are the only ones that will take an IOS past 12.2

mikej412

The only other thing to check before upgrading is the boot roms....

Versions in the 4s might need to be upgraded to use 3rd party memory upgrades...

Versions in the 5s are old.... but seem to work. I have 4 of these upgraded to max memory and flash and haven't had any problems (that I've found or noticed).

Versions in the 11s are current ....

When you upgrade the flash you'll probably boot into the stub IOS in the boot rom -- it had my configs from NVRAM and I was able to tftp a new IOS image to the upgraded flash without any problems.

Spudage

Thanks for the replies everyone.

From what you have said I have one 4Mb DRAM module, and one 8Mb Flash simm (I have checked and it is a single simm, leaving one spare slot).

If I replaced the 4Mb module with a 16mb module, what would the show version output say in regards to those two memory figures? 14336/2048?

mikej412, is it the following line that the versions you mention refer to?

ROM: System Bootstrap, Version 11.0(10c), SOFTWARE

mikej412

Spudage wrote:

ROM: System Bootstrap, Version 11.0(10c), SOFTWARE

Yep -- and you got a good one! You shouldn't have any problems upgrading memory.... at least from the boot rom chips.

Spudage

Thanks again.

One more question...

How much would expect to pay on eBay (or similar) for this sort of memory. Approximations in US dollars are fine, I'll convert that to my currency (AUD). All the stuff I've seen on eBay seems rather expensive for something that is used in old hardware (and they are all "buy it now" instead of auctions).

Also an expected used price for a DCE/DTE cross over cable would be handy too. The only cheap ones I can see on eBay will come from overseas and have a huge postage cost.

TheShadow

The cables are cheap but postage is high to get by the import duties. When I have ordered the declaration for the items were as books with low value.

Ram for 2500's can be found as cheap as 6 to 8 U.S. dollars for 16Meg. Memory can be high because after a period of time the 7 (if there are still that many) makers of the actual chips stop producing them. They always keep some of the finished silicon in tubes as backup for governments, special orders etc. but that is only half of the production effort. Once a chip goes off production then it is pretty much history. NASA in this country was buying 486's on ebay a few years ago because they could not find them anywhere else.