I have two 3550's interconnected by two gigabit links that are bound together. I also have two Vlans configured on both switches with a HSRP ip address. When the trunks are connected the switches complain about duplicate IP addresses on the LAN. It looks like a loop but the only connections between the boxes are the trunks.
Everything works fine with the trunks connected but the HSRP removed.
Often times complex troubleshooting issues are best addressed in an interactive session with one of our trained technical assistance engineers. While other forum users may be able to help, its often difficult to do so for this type of issue.
I sounds like you have a layer 2, due to the duplicate IP address messages. The MSFC will complain of duplicate IP address if it detects both routers as active at the same time or Layer 2 problem where the 3550 own packet gets reflected back.
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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...