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New Member

Uplinking using two ports

I have 3 Catalyst 2924 switches in my LAN. I would like to trunk two or more ports between them for uplinks, to eliminate that bottleneck.

Is there anything I need to configure IN the switch, or can I simply put crossover cables in any two ports?

Thanks!

  • Other Network Infrastructure Subjects
4 REPLIES
New Member

Re: Uplinking using two ports

You must configure two ports with FEC (FastEtherChannel) and put cables:

interface FastEthernet0/1

port group 1

interface FastEthernet0/2

port group 1

Without this configuration Spanning Tree will block one port.

New Member

Re: Uplinking using two ports

If you have more than one port, to do Fast EtherChannel, can we select the ports in random or it has to be in sequence. For an example group port 1,2,3 (sequence) or group port 5, 10, 22.

Regards,

New Member

Re: Uplinking using two ports

Hi, yes in Cisco there is a technology that they call fast-Etherchannel or Gigabit-Etherchannel, if you only put these 2 ports in parallel with this parameter disable, you will create a loop. Then you need to enable firts a group of FastEther-channel, and then add to this group the ports that create the logical tunnel, and that will be part of this group. You can group until 8 ports, in this way you can create a throughout of 1.6 Gpbs duplex.

New Member

Re: Uplinking using two ports

Hi ,

as default your switches will run spanning-tree

if you plug an additional link in it will cause a loop, spanning-tree will find this loop and will disable one of the ports. If the other port went down the second port will renable itself as a resillient link. You may have configured portfast if any stations are directly connected to the switch ports I advise that you ensure this is not enabled on the ports you wish to link. Next I would configure the ports to 100 full duplex, on a dual utp link this should give you a throughput of 400mbps. If you have no experience of the command line follow the guide to use the web browser...

dont forget to save the configuration...

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