Looks like the switch detected a second MAC address, and errordisabled the port: Apr 14 10:06:34 core-sw0 PortSec: %PORTSECURITY-2-PSECURE_VIOLATION: Security violation occurred, caused by MAC address 64:9e:f3:eb:6e:b0 on vlan 1 interface Ethernet4/21. Jeremy From: MICE Discuss [mailto:MICE-DISCUSS@LISTS.IPHOUSE.NET] On Behalf Of Todd Mueller Sent: Tuesday, April 14, 2020 4:06 PM To: MICE-DISCUSS@LISTS.IPHOUSE.NET Subject: [MICE-DISCUSS] Port was down Our (Velocity Telephone) MICE port physically went down at 10:06A and came back up at 2:31P today. Anyone aware of maintenance or anything else? Thanks! Todd To unsubscribe from the MICE-DISCUSS list, click the following link: http://lists.iphouse.net/cgi-bin/wa?SUBED1=MICE-DISCUSS&A=1