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3750 SMI and EMI images?

Hi all,

Would someone mind clarifying how the SMI and EMI images work on 3750 switches? I have read the following in the 3750 software installation guide:

The Catalyst 3750 switches are shipped with either of these software images installed:

=B7 Standard multilayer image (SMI), which provides Layer 2+ features (enterprise-class intelligent services). These features include access control lists (ACLs), quality of service (QoS), static routing, and the

Hot Standby Router Protocol (HSRP) and the Routing Information Protocol

(RIP). Switches with the SMI installed can be upgraded to the EMI.

=B7 Enhanced multilayer image (EMI), which provides a richer set of enterprise-class intelligent services. It includes all SMI features plus full Layer 3 routing (IP unicast routing, IP multicast routing, and fallback bridging). To distinguish it from the Layer 2+ static routing and RIP, the EMI includes protocols such as the Enhanced Interior Gateway Routing Protocol (EIGRP) and the Open Shortest Path First (OSPF) Protocol.

We have been purchasing both EMI and SMI switches for use in the same stack. We have been using the "arc copy-sw" command to synchronise IOS versions across the switches.

Does this mean we have been copying EMI images onto SMI switches? Or vice versa? Am I confusing images with IOS versions? Are they the same thing?=20

Many thanks,

Reply to
thefunnel
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From what I've seen on the newer Cisco switch hardware, the SMI and EMI (and Advanced) images are all identical, even though the software download area makes it sound like they are all different. I've binary diff'ed some of the files and they are the same.

Looks like there is some cookie file on the switch that controlls which license you really have, and you are fine copying around the images like you have been.

Reply to
Doug McIntyre

We've changed from SMI to EMI on switches and all we did was download the correct file. The hardware is the same, just SIGNIFICANT licensing costs for the extra software capabilities.

DiGiTAL_ViNYL (no email)

Reply to
DigitalVinyl

I've tested this out for the same thing for a 3560 and a 2950T in the lab, and they don't increase their license values after doing so.

As I've said, I've binary diffed the files presented for download for the different licenses for these two particular ones without any difference what-so-ever.

OOTH, I was successful to do this on one of the older switches in a lab situaton once. I don't remember the specific model, it was the first model to offer the SMI vs. EMI licenses vs. the older desktop/enterprise license model.

So, perhaps one model still lets you, but in general, the newer models do not let you.

Reply to
Doug McIntyre

This was a 3750-12G model, probably purchased early 2005. We needed to implement multicast routing features and the commands were not present in the SMI image. We loaded the EMI and had access to them. We may have used a tar file to do the upgrade, that includes an INFO file and the htmls. So perhaps that was important in some way.

DiGiTAL_ViNYL (no email)

Reply to
DigitalVinyl

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