I read quite a few documents on configuring SPAN on a cisco switch but none of them mention any limitations or any kind of CPU load it can have on a switch. I need to configure this on one of our switches and would like to know if there are any implications related to SPAN.
If you are running IOS 12.2(19) or later release, you can monitor the CPU to see if there is any impact when SPAN is turned on.
Have a look at this doc:
I actually do not want to reach to that stage where after turning on SPAN I run into CPU issues hence I wanted to know if there are any issues with SPAN.
I have used SPAN earlier in production networks but the network where I configured SPAN was not huge enough. The current network has lots of VLAN and traffic passing across so I am kinda skeptical.