Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

Switch:  Combined Ports

Posted on 2007-04-01
2
Medium Priority
?
256 Views
Last Modified: 2010-04-12
Hello Experts,

I have a question in regards to linking two switches together.  Lets say I have two Catalyst switches, both are 3750's and I connected fa0/10, fa0/11and fa0/12 from SW1 to SW1 respectively.  Let say that each port is running at 100Mb.  Does this mean that the total link between the switches is 300 Mb?  If not, how can this be achieve via CAT5?  What commands do I need to read up?

As always, thank you in advance for your time on this matter.
0
Comment
Question by:coperator
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 
LVL 5

Accepted Solution

by:
mdrichards earned 1000 total points
ID: 18834212
Yep you certainly can, although with 3750's you'd wanna use the builtin backplane as it is much faster.

If you want to group standard ethernet ports together you want to set up an "EtherChannel"

You basically group fa0/10, 0/11 and 0/12 into a "channel-group" making them a virtual 300 Mb channel.

Check out the links below

http://en.wikipedia.org/wiki/EtherChannel

http://www.cisco.com/en/US/tech/tk389/tk213/technologies_configuration_example09186a0080094647.shtml
0
 
LVL 50

Assisted Solution

by:Don Johnston
Don Johnston earned 1000 total points
ID: 18835556
>Does this mean that the total link between the switches is 300 Mb?

No. Spanning tree will block all but one link resulting in a single, operational 100mb link.

>If not, how can this be achieve via CAT5?

The closest you can come to doing that is etherchannel. However, Etherchannel groups must be 2, 4 or 8 links. If you try it with 3, the best outcome would be that only 2 of the links would carry traffic.

Even if you use a 4 port etherchannel group, it will still not give you a 400mb "pipe" between the switches. The traffic between two end devices (say A and B) that cross the etherchannel will use one of the 4 fastethernet links. The traffic between C and D may use a different link.

The bottom line is that etherchannel doesn't give you a faster path between two switches. It's really just a way of trying to get around spanning-tree blocking the redundant ports. At the end of the day, if you need more bandwidth, a faster link is the only way to go.
0

Featured Post

On Demand Webinar: Networking for the Cloud Era

Did you know SD-WANs can improve network connectivity? Check out this webinar to learn how an SD-WAN simplified, one-click tool can help you migrate and manage data in the cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The worst thing when starting a new job is when the previous Network Administrator left behind no documentation. How do you get into the devices? If you've been in this situation or just accidently mistyped your password, this article will hopefully…
This article will show how Aten was able to supply easy management and control for Artear's video walls and wide range display configurations of their newsroom.
Do you want to know how to make a graph with Microsoft Access? First, create a query with the data for the chart. Then make a blank form and add a chart control. This video also shows how to change what data is displayed on the graph as well as form…
In this video you will find out how to export Office 365 mailboxes using the built in eDiscovery tool. Bear in mind that although this method might be useful in some cases, using PST files as Office 365 backup is troublesome in a long run (more on t…

721 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question