Cisco NVram vs Flash

[cisco8887]

Hi Guys,

If one types show version on a switch is returns lots of informational text plus below

512K bytes of flash-simulated non-volatile configuration memory.

Does this mean the nvram is flash ? I always thought NVram is a chipset soldered in and not part of flash.

following from above, if yes then can one change the size of the nvram to a higher or smaller amount ?

Many thanks

[Mark Malone]

Theres a couple of good answers in this link may clear it up for you

https://learningnetwork.cisco.com/thread/65751

[cisco8887]

I did read that article before but thanks again for posting it

It does say the 2600 router flash and nvram is the same physical device and there was an interesting post at the end saying flash is good for read and nvram for ram and it is only a matter of time before nvram is replaced by flash

I think the switch I am working on, has the same device for both nvram and flash

it is also further confusing me when once can set the size of nvram using  "boot buffersize 524288".

if nvram is eprom and it is fixed size how can you change the size?

[Mark Malone]

in 2600 nvram and flash are the same in other devices there seperate

NVRAM is used for writable permanent storage of the startup configuration. It is an EPROM, except in the 2691, where the startup configuration is stored in the same Flash device where the boot code is loaded. Flash: Flash is used for permanent storage of a full Cisco IOS software image in compressed form

NVRAM is a type of flash --The best-known form of NVRAM memory today is flash memory

good post on nvram

http://www.infoneedle.com/posting/9302

[InayathUlla Sharieff]

The flash is where the IOS image is stored in a compress file, (.bin) and sometimes different IOS are stored on the flash.  A good reason for this is if you are running one version, and want to upgrade, keep the older one on there as well.  If you upgrade, and find that for some reason it don’t work, like being corrupted, then you can reload the older one.

The NVRAM, is the uncompressed file from Flash.  The boot up process will look here first for a file to load.  Changes can be made to the startup-config, by “copy running-config start-up config”.

Yes Flash and NVRAM are similar, but they do different functions. 

HTH

Regards

Inayath

[cisco8887]

sure I get that but is nvram same as flash , are they physically the same device ?