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Tag: STP

November 13, 2026

Cisco Catalyst STP Troubleshooting: IOS XE Commands for Rapid PVST+ and MST

A Cisco Catalyst trunk can be physically up and forward traffic for one VLAN while spanning tree blocks another. To find out why, inspect the affected VLAN or MST instance and correlate the port state with the switch log and trunk configuration. This guide uses Cisco Catalyst 9300 and IOS XE Dublin 17.12.x, including the […]

November 13, 2026

Aruba AOS-CX STP Troubleshooting: Commands for MSTP and RPVST+

A redundant uplink on an Aruba switch is discarding frames. Is that the expected backup path, or did a protection feature intervene? Start with the spanning-tree instance that carries the affected VLAN, then compare its root, port roles, and recent topology changes against your design. This guide uses Aruba CX 6300 switches and the AOS-CX […]