Juniper EX Flooding on STP Topology Change

juniper-junosspanning treeswitching

I have a relatively large layer 2 network where port flapping is not uncommon. I am using Juniper EX 2200 switches, which clear out the mac-forwarding table on a topology change. It is not uncommon for ports to flap in our network, devices reboot, etc.. Each time a port flaps, a TC is sent throughout the network and all of my EX switches flush out the ethernet-switching tables. This creates a pretty large flood while the switches re-learn. Has anyone experienced an issue similar to this? Do you have any suggestions to limit the flooding that happens after an STP TC? Is there anything that I can configure on the EX switches to limit the flood?

Thanks!

Best Answer

TCNs are only generated from non-edge ports when they receive a BPDU. Verify that your access ports are configured as edge ports under your spanning-tree config.

set protocols rstp interface ge-0/0/0 edge

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