Difference between NVRAM and Flash?

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Can anyone explain to me what the difference between NVRAM and flash is? My understanding is that neither of these storage areas are cleared at reboot, but NVRAM stores the startup-config and flash stores the IOS image.... Is that correct?

-Adam

@Adam-Tyler said in Difference between NVRAM and Flash?:

Can anyone explain to me what the difference between NVRAM and flash is?

I'll give it a shot! NVRAM is actually RAM that without some power source will eventually dissipate the information in it. So when the device, router or switch is powered off, the NVRAM maintains configurations because there is a battery still providing low voltage to keep that RAM active.

Flash is equivalent to the HDD of an end user's system or a server. Data is written to it and can be maintained without additional power source. Usually, not found in a great amount on cisco devices.

My understanding is that neither of these storage areas are cleared at reboot, but NVRAM stores the startup-config and flash stores the IOS image.... Is that correct?

Yes, that is the traditional usage. They were purpose driven type of memory usage so they didn't need to have a tremendous amount of capacity or speed.

Thanks for the great question and thanks for being a member!

Thanks Ronnie for your complete answer!

-Adam