catalyst switch ios upgrade from 12.2 to 15.2

[yong khang NG]

HI All

what is the step i need to concern if i planning to update ios 12.2-55 SE [x] TO 15.2 -4E[X]

I know is a huge jump, and i cross check the release note, and cisco software download, the version ios 15.2 - 4E6 is mark as recommended release (a magic star).

While google i read many thread showing hiccup after upgrading to ios 15.x etc etc.

My question: will it have any config syntax changing? How long should i expect it finish the whole cycle? what need to look, as i am now at least comply minimum ios 12.2 software. Is it simply copy the binary to the flash, change the boot path and reboot, the rest let the machine handle then, am i correct?

Any other matter i should know? Field experience and comment most welcome.

Thanks

Noel

[Seb Rupik · Accepted solution]

Hi there,

You should be fine to jump from one version to the other. Check the flash size requirements of the 15.x image. Your switch may be so old that it will not be able to fit it on.

The jump from 12.x to 15.x will incur a lot of microcode updates. These can take anywhere fro 30 to 45 minutes depending on platform.

Regarding syntax, it is unlikely that you will come across anything incompatible. You may have some depreciated commands. Pay attention to the log during bootup and it will warn you about them.

cheers,

Seb.

[Leo Laohoo]

What is the exact model of the switch? Not all switches can support 15.X.

[yong khang NG]

Hi Master Leo

Yup, i did my research check on the flash and model, only the qualified and status not EOS/EOL

My concern is, 12.2.55 to 15.2.4, what is the upgrade path? and 12.2.58 to 12.2.55 (seems like backstep to me), but 12.2.58 is not support anymore.

I just want to set the expectation, like possible challenge (take long time to load during upgrade, syntax different etc etc)

yah, thats my concern and question anyway

[Leo Laohoo]

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@yong khang NG wrote:
My concern is, 12.2.55 to 15.2.4, what is the upgrade path? and 12.2.58 to 12.2.55 (seems like backstep to me), but 12.2.58 is not support anymore.

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You're not answering the most important question:  What is the exact model of the switch/switches? 

Not all switch/switches can support 15.X.