S4 with 1 io module and 1 fabric module, expected failure behavior?

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I need to do some redundancy planning. On a S4 with 1 IO module and 1 fabric module what will happen if:

1.) The fabric module fails ?
Would the entire switch fail ?

2.) If the IO module fails ?
Would we only loose connections on the IO module?

Apologies if this seems straight forward. I just need to make sure that the behavior I expect is what actually will happen.

Thank you,
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Posted 3 years ago

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Straw, Glyn, Employee

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Hi Tino,

As the S4 chassis needs at least one fabric module for operation, if a chassis is running with only a single fabric module and that fabric fails, all traffic through the system will stop forwarding. For this reason, the use of redundant fabric modules is recommended for these models.

An IO module failure will not affect any other part of the system. Obviously any uplinks would need to be lags spread across multiple blades in order that they are not affected.

Best Regards