Wired Intelligent Edge

Hi

We have a small network and three differing switches supporting this.  THe core is a 2910al POE acting as GW.  We have two others - 3com 2952 and a v1710 in a chain config i believe. 

We are possibly expanding below so will need another switch to support this office.  It will be approx 10m away from the otjher switches.

We are looking at the 2930F series (x4 devices - all 48g POE) and leveraging the VSF in loop/ring mode.

Have scanned the config guides and all looks ok.    Just wondering if anyone hs used this in the real world and noted any improvements?  Use transcievers or rj45 ports, or both?  

Also whats best way to migrate switches over?  Weekend?  Same config i.e. DGW IP the same or different? 

Thanks

Hi,

you can go that way.
If switches are too far apart, it's often better two split into more than one VSF. E.g. between two buildings/locations. It can be difficult to get the extra links for multi active detection.

You have to use 10 Gig links. The SFP+ ports.
So no RJ45. But you can use DAC-Cables or fiber connections. You can mix them and use what ever fits best for the distance between the switches.

For migration I prefere to add new switches in parallel and connect to old switches at one place. But you have to think about spanningtree while doing this. E.g. keep old and new seperate by uisng BPDU-Filter. Pro: no root changes in old world. Con: no multi device redundant connection between new and old.
That way layer two is in place and can be tested before changing everything.

At a later point in time routing has to be moved from old to new. I would keep default gateway IP, cause otherwise you'd have to change that on every device connected to the network. But that causes donwtime. Since you can prepare configuration snippets for this, downtime should be far below 30 minutes. So this can be done in the evening, if you do not have business running 24*7. Just copy snippets into CLI-Session.

Regards, Jörg

I belive we can turn STP off, as it was off before.  I also believe we dont need STP for VSF, correct?

So, Switches 1 - 4 in VSF, configured:

Switch 1 - 2x DAC - to Switch 2,

Switch 2 - 2x DAC - to Switch 3,

Switch 3 - 2x SFP - to Switch 4,

Switch 4 - 2x SFP - to Switch 1????

Thnaks

If I'm not mistaken you can't have VSF Links (between all various VSF Members) deployed using different speeds (if you setup some VSF Links using SFP Transceivers that mean basically to use 1 Gbps links - aggregated or not - if, instead, other VSF Links are set using DAC or SFP+ Transceivers that mean 10 Gbps...so there will be a speed mismatch)...you instead must use/mix SFP+ and/or DAC freely.

Is this 100% accurate? 

Hi,

as far as I remember, yes.

But even if you could mix speed, you shouldn't do.

Your VSF links would become a bottleneck in your network.

From design perspective I always would use 10 Gig (or above) for VSF-links, where end devices wil communcate at 1 gig rates.

If budget is an issue, you could use just one connection between the switches. If you close the ring, you are still redundant. But I have to say, 

that I would prefere to have two links between the switches.

From your ??? above:

Yes, you should close the ring and connect switch 4 back to switch 1.

Kind regards, Jörg

Please see the 2930F Management and Config Guide under "VSF Restrictions" - Pg 755 

https://support.hpe.com/hpsc/doc/public/display?docId=a00050273en_us

VSF port restrictions:

◦ Must be 10Gbps/1Gbps.

◦ A VSF link can only comprise ports with the same speed; either all 10G or all 1G. A VSF port speed which does not match with the global port speed, will be in a down state. The command show vsf link detail will display an error message.

◦ Maximum eight ports can be configured on one VSF link.◦ VSF ports must be directly connected and there should be no transit devices between members.

All VSF link ports must be the same speed, in the case of the 2930F, either 10g or 1g.  As mentioned above, a VSF stack should always be configured in a ring topology.  

As of 16.06, you can now stack up to 8 members in a 2930F VSF Stack.

Justin

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@chiltd wrote:

Is this 100% accurate? 

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Yes, it is.

As Jörg and Justin Noonan confirmed, the requirement is that the entire VSF links "chain of connections" (VSF topology doesn't matter: that's valid for Ring or Chain VSF topologies) need to be setup using entirely either with 10G physical links (as example using SFP+ Transceivers and/or DAC Cables) or entirely with 1G physical links (as example using 1000Base-T cables and/or SFP Transceivers).

It's a matter of not creating bottlenecks along the entire VSF "chain of connections".

This was discussed here also.

Thanks for replies.  I will accept solution soon.  We are just deciding on best option, new switches inc VSF or stary as-is and utilise an old 2910al poe in remote location saving c£6k.