Hello everyone!
I work for an ISP and on access layer we use ring topology.
We use rstp for l2 redundancy on access layer and REP(resilient ethernet protocol) on core/aggregation layers.
To tunnel BPDU between edge switches in the access ring we use l2protocol-tunneling(https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/l2pt.pdf) feature on ME4924 ports that faced to access switches.
The problem is convergence time is too long if any l2 topology change happens. For an example, if I shutdown ME 4924 port that linked to primary root, then rstp convergence time will takes about 2 mins.
We have no hubs or stp 802.1d enabled devices in the topology, portfast feature is configured on access ports. So I can't understand why this is happening.
Can anyone help? :)
