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IOS release 15.X ????

Trying to figure cisco's new release and why they jumped from 12.X code to 15.X code. What happened to 13 and 14 . :-) I see this out there for the 2800 series now . It's a ED release. It looks like they made 15.X the mainline code for the 12.4T train , wonder why they skipped 13.0 or 14 ? Sounds like they are taking it down to 2 trains either maintenance or T trains , about time they simplified it !!!


VIP Super Bronze

Re: IOS release 15.X ????


I think Cisco IOS developers must be superstitious. I thought they may announce 13 around Halloween.

As for ver 14, apparently that is also an unlucky number in Asia.



Re: IOS release 15.X ????

Correct, 12.4T i moved to 15.X.

There should be releases every 4 months or so.

IOS 15.0 doc:

The doc with the new features:

There is also the concept of having 1 IOS image with all featureset on the device running 15.0 and a license will activate either features on the router. So no more need to download and upgrade to another image.

As far as why no 13 nor 14, no idea. It may come later for main trains, I dont know.


Re: IOS release 15.X ????

It still looks like there is a bunch of different images you have to choose from adenterprise,ipbase,ipvoice etc... so is the single image in the future still ??? The idea seems like an administrative nightmare a lot of times the actual equipment is ordered by people with lesser networking knowledge and if you are under tight time constraints which you always are this will be a real hassle if the features you need aren't activated.