STP Issue?

Hi everyone,

I have a network with two Dell switches, connected to a Cisco switch. The main core switch is an older Cisco switch.

The Dell switch keeps having an issue with disconnections (briefly) of the 4 Dell servers connected to those Dell switches. The servers are running VMware 6.7 with VSAN (VxRail) have 4 VLANs on them and the Dell switches are connected to the Cisco switch using port-channel (for redundancy).

The Cisco switch has SVI installed on 3 VLANs that are also on the servers.

There are other Cisco switches on the network. I opened a ticket to work on it back in November, but other than an upgrade of all software and firmware, not much has changed. They may be getting disconnected when a TCN is received and the MAC table is cleared but not sure why I seem to be the only one having the issue.

Are there any suggestions for what I can check or change? Dell and Cisco switches are running RSTP, but I never set up the network originally, but I have noticed there are a couple of switches running MSTP.