IOS and NX-OS Platform Identifiers
I was preparing a presentation the other day about the high level differences between IOS, IOS-XE and NX-OS and one of the things I included in the presentation was the various platform and branch identifiers that’s used in each OS. It’s just a bit of trivia that I thought would be interesting and might come in handy one day. I’m posting the information I collected below so everyone can reference it.
IOS
For IOS, you can see the platform identifier in the filename and the “show version” output. If we take an example version string, 15.1(2)SG2, and break it down, here’s what each digit in the string signifies:
| 15 | .1 | (2) | SG | 2 |
| Major release number | Minor release number | New feature release number | Branch/train/platform identifier | Maintenance rebuild number |
The branch/platform identifier can also be seen in the IOS filename:
cat4500e-entservicesk9-mz.151-2.SG2.bin
Here’s a summary of the branch identifiers in IOS 15:
- M/T – 800 Series ISR, ISRg2 (1900, 2900, 3900), Connected Grid Router 2000
- S – 7600 Series Router, ME 3600X, ME 3800X
- GC – 5900 Series Embedded Router
- SE – Catalyst 2960, 3560, 3750, IE 3000 Switches
- SG – Catalyst 4500E (Sup 6E and earlier)
- Continue reading

