We had an "Event" on our process network at the mill yesterday. I connected a new WS-C3560V2-48TS-S to our network and we lost communications with all of the other switches.
The core is a stack of 3 WS-C3750 switches, one is a -24TS-1U and the other two are -12S-S. These connect to 10 WS-C3560G-24TS and 5 Rockwell Stratix 8000 (IE3000) over fiber. I am planning on replaceing two 24 port switches with the new 48 port. I had the switch configured and running at my work bench. It was connected to the network with one sfp module and ran all weekend with no issues. Yesterday afternoon I took it to the network cabinet and installed it. I powered it up and connected two sfp modules to the fiber patch panel and made the connection at the core stack.
Everything looked OK. I had communication link lights working on everything. Within minutes, we lost communication with every switch connected to the core stack. I shut down the new 48 port switch and the network slowly came back up.
The new 48 port is configured with Flex Links for the fiber redundancy protocol and was connected to each of the 3750G-12S-S stack members.
I though it might have been a power issue but the stack is UPS protected and shows it has been up for over 10 weeks. I'm not even sure "Crash" is the best decription for what happened. The new switch has a high enough IP address that it would not take over as a IGMP Querier.
I'm at a loss to explain what happened but the boss wants an explanation. Can't be shutting down production. They don't like that...
Does anyone have any suggestions on what to look for or why adding a switch would take down all of the communications?
Any help would be appreciated.
Thanks
Pat
