From all I read on 802.1x with Polycom phones, the enabling should cause the phone to reboot, and all indications are that the phone requires a reboot. I could not find any good list showing what requires a reboot on a Polycom phone. Maybe you can ask Poly about this.
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Robert Wakefield-Carl
TTEC Digital, LLC fka Avtex Solutions, LLC
Contact Center Innovation Architect
https://www.Avtex.comhttps://RobertWC.Blogspot.com------------------------------