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Pancake_EffectFlag for United States of America

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How many Aggregated lines for two 48 port switches?

I have two cisco 48 port switches for our facility in a wire closet that is connecting back to our core switches in the data room. We used cat6 for everything and have auto auto duplex settings for the user machines.

We had a company put it all in for us.

For some reason they are only receiving 100mbps speed instead of gig.

We only have one cat6 running back to the core switches. Is this a possible reason why it's only negotiating at 100 mbps? How many aggregated lines do we need for it to negotiate at gig speed?

Is there a standard I can keep in mind for how many aggregated lines are needed per so many switches?

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A single uplink is not aggregated. An aggregated link is multiple ports bundled together  (ether channel) which means you would have multiple uplink cables.

Your ports are most likely fastethernet and that is 100Mbps. Depending on the switches you have, you may be able to bundle up to 8 ports as a port channel ((ether channel) but that would still be 800Mbps

This is an example of an aggregated link

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Another common reason for this is IP phones. If you have IP phones running at 100M, and your desktops are connected through the phones, you can only get 100M.
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Just out of curiosity and clarification, your saying that when you use fastethernet, you are stuck with only 100? PS We have a Cisco 3750 and a 2960.
Not sure who the question was directed at, but if it was me I can clarify. IP phones that are 100M phones usually have two ports on the back. One is to be connected to the switch, and the other is an additional switchport to allow you to connect a desktop/laptop. This way you only need 1 ethernet connection in an office or cubicle to get a phone and desktop connected. Now, if that phone only has two 100M ports, it can only connect to the switch at 100M and can only connect to the desktop at 100M. In the end, the end user will get 100M service as a result of the 100M phone that is stuck between them and the gig switch.
Also the 3750 and 2960 have both Gigabit and non-Gigabit models. We would need the exact model to determine the port speeds.

From the switch you might also be able to type show cdp ne to see what else is connected to it and on what port (in case it is IP phones).