These error messages do not necessarily indicate an HSRP problem. Rather, the error messages indicate a possible Spanning Tree Protocol (STP) loop or router/switch configuration issue. The error messages are just symptoms of another problem.
In addition, these error messages do not prevent the correct operation of HSRP. The duplicate HSRP packet is ignored. These error messages are throttled at 30-second intervals. However, slow network performance and packet loss can result from the network instability that causes the STANDBY-3-DUPADDR error messages of the HSRP address.
These messages specifically indicate that the router received a data packet that was sourced from the HSRP IP address on VLAN 114 with the MAC address 0000.0c07.ac01. Because the HSRP MAC address is 0000.0c07.ac01, either the router in question received its own packet back or both routers in the HSRP group went into the active state. Because the router received its own packet, the problem most likely is with the network rather than the router. A variety of problems can cause this behavior.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...