Mirrored data is modified on a SG200-08Ev2

[chrisvetter]

                   I am trying to use a GS200-08Ev2 switch to snoop data (Tx and Rx) from a network used to link secondary computers to a master computer for tool control.  The secondary computers connect to a central switch (SG100D-08).  That central switch is connected to the GS200 which is connected to a central computer, a secondary monitor computer, and the data collection computer.  I need to be able to snoop the data between the 2 switches with a passive collection system for fault detection (runs with all protocols and clients for the NIC disabled).  I can do this with a dumb hub but those are becoming rare.  I can also use a swith from another mfg but would rather not.  I can set the switch up to mirror the data but the data that comes out of the destination port has been modified.  It looks like there is an extra 4 bytes added to the beginning of each data packet.  The only configuration changes I have made are to the IP address of the switch and to enable mirroring - everything else is default.  I have also tried with all default settings except for the mirroring and get same results.  Any ideas on how I can clean this up?

[jeffrrod]

Dear Chris,

Thank you for reaching Small Business Support Community.

It's been several days since you posted your inquiry on this forum with no answer from any of the community members yet, therefore I suggest you to contact the Small Business Support Center to have an engineer assigned to your case and provide you a prompt and accurate answer;

https://www.cisco.com/en/US/support/tsd_cisco_small_business_support_center_contacts.html

I wish we could be a better a help but I am sure this support center will offer you the answer you are looking for.  Please do not hesitate to reach me back if there is anything I may assist you with in the meantime.

Kind regards,

Jeffrey Rodriguez S. .:|:.:|:.
Cisco Customer Support Engineer

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