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12-15-2010 01:49 PM - edited 03-06-2019 02:33 PM
What is the span (switched port analyzer) performance hit on a 3750 or a 3750X? I would like to mirror a source with high traffic volume to between four and six destination ports. I don't have a clear understanding of 3750 architecture. How is traffic moved from one port to another on the switch? What is the difference between span performance on a 3750 vs a 3750X? Am I better off using a network tap for this application?
Thanks.
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12-18-2010 06:21 PM
Hello,
In both Catalyst 3750 and 3750X, SPAN traffic is replicated in hardware, and should not have any impact at the process or control-plane level.
As SPAN is hardware-driven, you can have multiple destination ports for a given session, in Catalyst 3750 or 3750X.
I do not have any numbers to differentiate SPAN performance in 3750 and 3750X.
- Yogesh

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12-18-2010 09:40 PM
What is the span (switched port analyzer) performance hit on a 3750 or a 3750X? I would like to mirror a source with high traffic volume to between four and six destination ports. I don't have a clear understanding of 3750 architecture. How is traffic moved from one port to another on the switch? What is the difference between span performance on a 3750 vs a 3750X? Am I better off using a network tap for this application?
Thanks.
Hi,
As suggested by yogesh it wont be impact on performance with 3750 switch with muliple span destination,Just consider the amount of traffic which you are going to span is of high volume ..i would recommend span one by one destination and check the performance of the switch while going for all of the above on single shot.
Hope to Help !!
Ganesh.H
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12-18-2010 06:21 PM
Hello,
In both Catalyst 3750 and 3750X, SPAN traffic is replicated in hardware, and should not have any impact at the process or control-plane level.
As SPAN is hardware-driven, you can have multiple destination ports for a given session, in Catalyst 3750 or 3750X.
I do not have any numbers to differentiate SPAN performance in 3750 and 3750X.
- Yogesh

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12-18-2010 09:40 PM
What is the span (switched port analyzer) performance hit on a 3750 or a 3750X? I would like to mirror a source with high traffic volume to between four and six destination ports. I don't have a clear understanding of 3750 architecture. How is traffic moved from one port to another on the switch? What is the difference between span performance on a 3750 vs a 3750X? Am I better off using a network tap for this application?
Thanks.
Hi,
As suggested by yogesh it wont be impact on performance with 3750 switch with muliple span destination,Just consider the amount of traffic which you are going to span is of high volume ..i would recommend span one by one destination and check the performance of the switch while going for all of the above on single shot.
Hope to Help !!
Ganesh.H
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12-20-2010 11:42 AM
Thank you Ganesh and Yogesh for your replies. I am trying to decide whether I need to purchase a network tap for the proxies. I hear different opinions from different vendors. I don't want to introduce more hardware in the path if I don't need it.
ampowell

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12-20-2010 11:56 AM
Thank you Ganesh and Yogesh for your replies. I am trying to decide whether I need to purchase a network tap for the proxies. I hear different opinions from different vendors. I don't want to introduce more hardware in the path if I don't need it.
ampowell
Hi Ampowell,
I would suggest if you can go span for one by one to achive your results rather going for tap based solution.
Hope to Help !!
Ganesh.H
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