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Does a port mirror send ethernet frames out of the switch-port with the 802.1Q header bytes still on the frame?

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up vote 4 down vote accepted

By default, no. However, the behavior can be controlled on the monitor command; the encapsulation argument controls this. replicate will preserve the encapsulation type that the packet had in transit, while dot1q will force the 802.1Q header.

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Great answer. Thank you very much. – Ablue May 24 '11 at 5:35

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