How to configure core switch via stacking system?

[ashbyschool]

Hello people i hope you can help.

I am looking at options of swapping out our Core switch with a 9406R chassis with multiple blades etc. I am currently getting prices for this. However as i work in a large secondary school the budgets are tight so was wondering if buying separate switches in a stack would be more cost effective. I currently need 40x 1/10Gb SFP+ fibers. I have looked at 2 x WS-C3850-24XS-E 1/10Gbps switches with 640Gbps switching capacity. My question is if i stack them would i configure the ACL's and Routing etc on just one switch and use the second for the fiber as a layer 2 switch or do i need to configure both for layer3? I'm new to stacking technology so apologies if the answer should be obvious. Any advise will be much appreciated.

[fniccola]

ciao!

let me share with you a document regarding this topic:

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3850/software/release/16-9/configuration_guide/stck_mgr_ha/b_169_stck_mgr_ha_3850/configuring_cisco_stackwise_virtual.html

basically after you have configured the stack, you can manage it as if it were a single device, as you can read form the document, both devices are responsible for traffic forwarding (Data Plane), but only the Master switch manages the control plane

You can configure the stack as L2 or L3 device (depends to the release), stacking is a very powerful technology.

TKK

FabioN

[ashbyschool]

That's really helpful, thank you. I'll have a read of that this afternoon.

[balaji.bandi]

Stack means 2 Physical device acting logically 1 devices.

I would suggest to Look Cat 9300 (cat 3850 going to be end of life soon - you may negotiate nicely so you may have same price of 3850 with Cat 9300 switches?)

You can have combination of Cat 9300  for Layer 2 and core (kind of) and Cat 9200 (only for Layer2)

You can configure all in one stack switch.

[ashbyschool]

That's good advise. I will take a look at the 9300 and compare prices.

If i had 2 x 3850 in a stack and 1 switch failed say the master, would the routing and ACL's etc continue to work? Apologies for my weak knowlege in this area. Just starting to look at stacking now. 

[balaji.bandi]

yes in stack master fails all the information and configuration will be moved to standby(now active)

Note : Physical connection connected to master switch go down (if the end device have dual connection to switch1 and 2 in stack that is ok)

Look below stacking :

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

[Leo Laohoo]

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@ashbyschool wrote:
WS-C3850-24XS

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I would never use a WS-C3850-24XS as a "core switch":  Not enough grunt, not enough memory and 16.12.10a is the "last" firmware release.  

[fniccola]

ciao!

this is a good design guide for Campus Network, you can find all devices role, with respective models.

https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-campus-lan-wlan-design-guide.html

TKK

FabioN