Replicating packets

[jlajuarez]

How can i replicate packets that pass through Fast Ethernet 1 - 20 on a cisco switch to Fast Ethernet port 24 on the same cisco switch?

or

How do you replicate packets that are passing through all the switch ports to a single port on the same switch?

Is this possible?

[Eugene Lau · Accepted solution]

Hi There,

To replicate traffic from a group of ports (Source ports) to a single "monitor" port (destination port), you can use the SPAN feature of Cisco Catalyst switches

Reference:

http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a008015c612.shtml

Depending on the model of switch, there will be slight variations in performance capabilities and restrictions. With your requirements, the most common issue is oversubscription of the destination/monitor port. Monitoring many pipes and replicating traffic to the same sized pipe

Example.

If you monitor 10 x 100MB port = 1Gig of traffic is theoritcally possible and your destination port is also 100MB, then once the combined traffic > 100MB, traffic could be dropped at the monitor port.

Check the link out for a general overview and good luck!

HTH

Eugene.

[jlajuarez]

Thank you Eugene...

[Atif Awan · Accepted solution]

jlajuarez wrote:
How can i replicate packets that pass through Fast Ethernet 1 - 20 on a cisco switch to Fast Ethernet port 24 on the same cisco switch?
or
How do you replicate packets that are passing through all the switch ports to a single port on the same switch?
Is this possible?

The feature is called SPAN and is available on most of the Cisco switches. Depending on the model of switch you have go through the appropriate configuration guide to see how to configure this feature. An example is the 2950 configuration guide below:

http://www.cisco.com/en/US/docs/switches/lan/catalyst2950/software/release/12.1_22_ea11x/configuration/guide/swspan.html#wp1036686

Atif

[jlajuarez]

Thank you Atif...