2 switch stacks - fibre redundancy

[tjansen]

Hi All,

I am looking to have 2 access switch stacks - one in each building. The buildings are 300m apart so I will be using mmf between the buildings. I would like to have fibre redundancy so that the 2 stacks have connectivity in the event of a failure and I was wondering what the best way to do this was. Would I purchase sfps for 2 switches in the stack and just connect them ?

[Kasun Bandara]

first you need to identify which failure you are going to fix.

1. cable failure

2. module failure

3. switch failure

4. site failure

etc.

if you looking for cable failure, you can use 2 cables between 2 sites to connect stacks. and make sure each cable using different physical path to avoid failure in case of cable damage.

[tjansen]

Hi Kasun,

Thank you for your reply. I think we would look at module failure. Would that just involve 2 spf modules on each stack ?

[Kasun Bandara]

you can add 2 modules per stack. make sure distribute 2 SFPs between 2 switches in stack. and additionally you can make port channel to aggregate 2 links

[tjansen]

thanks - can I use the same mmf fibre to connect them ?

[Kasun Bandara]

yes. use OM3 or OM4 cable to connectivity

[balaji.bandi]

i would advise for redundancy use 4 SFP - 2 at each side, so they are in Layer2/ Layer 3 port-channel.

The buildings are 300m

check the SFP and cable you using :

https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/gigabit-ethernet-gbic-sfp-modules/datasheet-c78-366584.html