Patch Panel and cabling

[Bova_1980]

Hi All,

My question might be granted but I was not able to find a clear explanation.

Question: Assuming that I want to connect 2 switches hosted in 2 different room in a datacenter. They are working in peers (flex links) and offer (of course) redundant L2 connection to servers.

Topic: patch panel.

Each switch is installed in separate rack and connection between racks is with cables terminated in a  patch panel. 1 patch panel per rack.  My question is related on how many 'backbone' cables I need to connect between the 2 patch panels hosted in the 2 separated racks.

Assuming to use a 24 ports patch panel per rack,  assuming that I have 2 swicthes with 48 x 10Gb ports (fiber) , how many backbone cables do I need to use to connect the 2 patch panel? Just to make clear the connections I am thinking of:

• Each switch will have one or ore connections towards the patch panel (MultiMode cables)
• one or more connections between the 2 switches (ex: 4 x 10Gb) (SingleMode cables)
• the servers will have a dual mode connections towards the 2 switches (2 x 10 Gb) (MultiMode cables)
• patch panels connections?? How many cables? I just know that I will use SM cables, LR.

Please you can use a practical example with whatever kind of 24 port patch panel to clarify my doubt or addressing me to a specific link.

Problem here is that it is not clear to me how backbone connection between patch panel is working (and I am keeping looking for this info since days).

Thanks for the support.

BR,

Fabio.

[Philip D'Ath]

How many servers are there that need dual connecting, since you need a cable per server?

[Bova_1980]

How many servers are there that need dual connecting:

Assuming 20

• Each switch will have one or ore connections towards the patch panel (MultiMode cables)
• one or more connections between the 2 switches (ex: 4 x 10Gb) (SingleMode cables)
• the servers will have a dual mode connections towards the 2 switches (2 x 1 Gb ) (MultiMode cables) (I wrongly write 2 x 10Gb, reality is 1 Gb)
• patch panels connections?? How many cables? I just know that I will use SM cables, LR.

[Philip D'Ath]

I think I would put in 32 ports if it was me (or 48 if cost is not an issue).  It sounds like there might be quite a bit of potential variation.

[Bova_1980]

How did you reach this number? I just want to see the logic behind this calculation. Thanks so far for your time.

[Philip D'Ath · Accepted solution]

You have 20 servers, so there is 20 patches straight away.  You have a number of devices which may require more than 4 patches. Patch panels usually come in 8 port modules, so the next jump up after 24 is 32.

[Bova_1980]

Many thanks.