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I want to link a Cisco 3560G switch with a WS-C3560G-24TS-S ( From what I understand, I can use either two regular switch ports to uplink (separate ports for TX and RX) or go with SFP (GBICs?) and then either copper or fiber.

That all seemed pretty simple until I looked at the SFP options. Wow... I think I need 4 SFP modules to link two switches but which brand? Do I need CWDM? or SFP+? It seems way simpler to just use a couple patch cables on ports 23 and 24 but don't I want a faster medium for the uplink ports?

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up vote 2 down vote accepted

You can use the regular copper ports or the SFP's (which could be fiber or copper depending on the GBICs you insert into them). Stay away from CWDM, and most GBIC suppliers these days will give you some level of compatibility to the device you are looking to use it in. Don't even consider messing with the SFP ports unless you think you will push the port density usage of either switch, or the two switches are more than 300 feet apart from each other (standard limit of quality on a copper Ethernet link). To do so (use a fiber path) when these needs aren't present is to spend money and time working with a portion of the network configuration that is useless for you to pursue. Fiber is less-forgiving than copper, costs more, and has more working parts involved that could break and cause you to have a frowny-face.

Do you want a fast connection between the switches? Yes. Do you need more than one Gbps between the two switches? Depends on what the largest amount of traffic you expect to transmit across them at any given time. If it comes to about %75 or more (750Mbps) or you wish to have fault-tolerance between the switches, then it's a good idea to have two links configured as LACP so that they appear as a single 2Gbps highly-available path.

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Good answer. Isnt pagp = etherchannel = preferred cisco to cisco way though? – 3molo Feb 7 '13 at 19:14
To answer 3molo, I think that's debatable in either direction. If you plan to never use anything other than Cisco (not just in this setup, but anywhere where there are multi-port uplink switching needs) then I'd say pagp/etherchannel would be fine. But if you plan on using other vendors (or already do) then I would usually recommend a non-proprietary protocol to use so that you bring less pain in your mind in the future when you have to mentally switch gears in your network administration work. In these circumstances, do what makes your life easier :) imho. – danstermeister Feb 7 '13 at 19:24
Some terminology: You insert an SFP into an SFP slot and a GBIC into a GBIC slot. The two are not the same. – Sven Feb 7 '13 at 19:26
to SvenW : oh goodness, you are correct. In my haste I jumbled that with slots and PICs and such, apologies. – danstermeister Feb 7 '13 at 19:29

You can use a couple of patch cables and create a bond/trunk between the two. It's fine. The 3560's aren't stackable.

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