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IOS /Memory Requirements

control

Hi,

Is there a minimum Flash/Main Memory requirement for each Cisco IOS, the same as there if for Windows O/S e.g

If I wanted to, for example load the latest IOS for a specific router, does it need a minimum amount of RAM/Flash RAM? Is this info on some sort of table format anywhere if so?

Thanks

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Comments

wastedtime

Should be able to find out here: Cisco Feature Navigator - Cisco Systems

Although I don't know of a table.

control

Hi, have had a look at that in the past but has no memory requirements.

So for example - If I look up the 1751 router the highest major release is 12.4. Now does this mean that the router with the shipped default RAM Sizes can take 12.4, or would it need to be loaded up with the highest available RAM it can take?

Somnipotent

control wrote: »

Hi, have had a look at that in the past but has no memory requirements.

So for example - If I look up the 1751 router the highest major release is 12.4. Now does this mean that the router with the shipped default RAM Sizes can take 12.4, or would it need to be loaded up with the highest available RAM it can take?

not necessarily. when you order direct from cisco you specify your needs based on your network requirements and your sales rep will cater your IOS ver and device to your needs. just because it CAN support a 12.4 doesn't mean it WILL. in many cases it just requires a flash/dram upgrade which is fairly cheap on ebay and you'll be good to go.

tiersten

control wrote: »

Hi, have had a look at that in the past but has no memory requirements.

So for example - If I look up the 1751 router the highest major release is 12.4. Now does this mean that the router with the shipped default RAM Sizes can take 12.4, or would it need to be loaded up with the highest available RAM it can take?

You need to select a specific version and feature set before it tells you what flash and RAM you need as it will differ based on those criteria.

Slowhand

control wrote: »

Hi, have had a look at that in the past but has no memory requirements.

That's not correct. Once you've picked your platform, your IOS version, and your release, it'll not only tell you all the features available but also how much memory is required as a minimum to run.

For example, here's the minimum requirements for c1700-adventerprisek9-mz.124-25c.bin, which is IOS version 12.4(25c) Advanced Enterprise Services: 128MB RAM and 32MB Flash.

When you buy a router, you'll have to find out from the seller how much RAM and Flash memory it has so you know if you need to upgrade. I once bought a 1721 router that only had 16MB of Flash memory, which is not upgradeable, so I was out of luck when it came to installing the IOS and had to settle for 12.4 IP Base instead of Advanced Enterprise Services.