Seek for Advice: using 2960S vs 2960G to achieve resiliance

[kufatkufat]

Hi,

I would like to add some resiliant features to the existing LAN.  Initially, I proposed to use 2960S switches stacked together (see proposed network architecture 1 below).  However, owing to budget constraints, I have amended the proposal to use 2960G switches (see proposed network architecture 2 below) which do not have stack feature.  If link aggregation is not a must, may I know if architecture 2 a feasible solution to achieve resiliance?  Also, may I  kown if RSTP can be adopted?

Thanks a lot.

Dennis

[Joseph W. Doherty]

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Posting

"If link aggregation is not a must, may I know if architecture 2 a feasible solution to achieve resiliance?"

It is, if fact a classical approach before the advent of stackable switches.

"Also, may I  kown if RSTP can be adopted?"

Yes, since some form of STP is required for architecture 2.

PS:

Not having the stackables, you lose some nice features.

In architecture 2 you could also link the two switches, if close enough to stack, with copper.

[Jon Marshall · Accepted solution]

Dennis

The only thing i would add to Joseph's post is i can't see the need to interconnect the 2960 switches on each floor with a fiber cable because they are not actually stacks as such. You don't really get any more redundancy by interconnecting them. Because on each floor the 48 port switches are connected to both then if one of the 24 ports switches there is an alternate path.

This would also simplify STP.

Jon

[Joseph W. Doherty · Accepted solution]

Disclaimer

The  Author of this posting offers the information contained within this  posting without consideration and with the reader's understanding that  there's no implied or expressed suitability or fitness for any purpose.  Information provided is for informational purposes only and should not  be construed as rendering professional advice of any kind. Usage of this  posting's information is solely at reader's own risk.

Liability Disclaimer

In  no event shall Author be liable for any damages whatsoever (including,  without limitation, damages for loss of use, data or profit) arising out  of the use or inability to use the posting's information even if Author  has been advised of the possibility of such damage.

Posting

Jon is correct, the non-stack link between the two 2960Gs adds little to practical resilience although if the uplink path fails from one of the 2960Gs to the 3750X, the link from one 2960G to the other negates the need for its traffic to transit one of the 2960s.  Since this is only performance consideration for a particular failure scenario, if I had a gig copper port to spare on both 2960Gs, I would likely configure the link, but probably not for a gig fiber port because of the additional cost.

[kufatkufat]

Thank you very much for the really useful advice from JosephDoherty and Jon.Marshall.  Before viewing your replies, I didn't realize that there was no need to interconnect the two 2960G if Cicso stack cables were not used.