Stacked Switching and Layer 3 devices

[jayu]

We're looking into a three-switch solution.  9300L series, all three.  We're wanting to run this in a stack with one being a Layer 3 device and the other two standard Layer 2 switches.  Need to know if it's possible to run all three in one stack or if we need to split it.  Hoping to cut down on config/management time and complexity while also providing a quick backup to the Layer 3 should it go down.  Thanks in adance!

[balaji.bandi]

You can do stacking with all Cat 9300L Model switches.

Stack means - 3 Physical switches, become Logically 1 Switch.

in 3 switches, one acts as Master - it has all config Layer 2 and Layer3  (rest 2 switch act as a member do not hold any config)

Once the master switch failed next slave switch becomes master electing stat functioning as expected.

you can configure port or SVI layer 3, and some ports only Layer 2 as access ports.

Look white papers :

https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9300-series-switches/white-paper-c11-741468.html

[jayu]

Thanks!  I'm reviewing the whitepapers you recommended.  

[balaji.bandi]

sure let us know anything you need further help!

[Leo Laohoo]

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@jayu wrote:

We're wanting to run this in a stack with one being a Layer 3 device and the other two standard Layer 2 switches.

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This does not make any sense. 

The entire stack act as one.  The entire stack is either Layer 2 or Layer 3 and not "split".  

[Joseph W. Doherty]

As noted by other posters, a stacked switch logically runs as one device.  However, it's possible, licensing might be per physical switch and all switches in the stack might require the same license.  If so, it's further possible a more "advanced" (and usually more expensive) license might be required for the L3 capabilities you desire.

If this is the situation, you could run L3 on just one switch (with a "better" license) vs. just L2 on the other two switches (with a more "basic") license, you might be required to run the L3 switch, just by itself, but could run the other two switches, stacked, as a single "logical" L2 switch.

(BTW, way back with the 3750 series, you could mix license levels in the stack switch members, and the stack would run the "best" licensed IOS for the stack, as one logical device.  However, I believe [?] Cisco's later stackable switches no longer support this.  [Likely @Leo Laohoo would know for sure.])

[jayu]

So, in case anyone is interested still, a pre-sales engineer confirmed that to do all three in a single stack, we'd have to have the L3 license for all three units...not a cost the company is willing to spend if we don't have to.  So, one L3 and one 2-unit stack is it!  Thanks for all the feedback!