Multiple Spanning Tree Protocol (STP) Enhancements

ExtremeXOS 22.2 includes several Spanning Tree Protocol (STP) enhancements:

Default operational mode for STP domain "s0" is MSTP CIST mode (instead of 802.1D mode). This is enabled now by default for the Default VLAN.
The default port mode for user-created STP domains for Dot1d and Dot1w operation mode is Dot1d, instead of EMISTP.
With sharing and STP configurations established, disabling sharing no longer removes the STP port configuration for the configured master port and it preserves certain configuration attributes and restores them when the port is recreated.
A configured port's STP properties are preserved when the port is moved from one VLAN to another, provided the new port gets associated with same STP domain.
STP operational mode can be changed while VLANs are associated with an STP domain. Mode change is allowed only for CIST domains.
A check is added to avoid flooding of BPDUs to the slow path in some cases where STP is enabled. Discarding of STP/PVST+ BPDUs in slow path when STP BPDU forwarding is disabled.
Multiple Spanning Tree Protocol (MSTP) is now enabled as a factory default. When you boot up a switch for the first time, you are informed that MSTP is enabled by default. You can change this setting if desired.

Supported Platforms

Summit X450-G2, X460-G2, X670-G2, X770, and ExtremeSwitching X870, X440-G2, X620 series switches.

Changed CLI Commands

The default port mode for user-created STP domain is Dot1d in the following command:

configure stpd stpd_name default-encapsulation [dot1d | emistp | pvst-plus]

The following command now allows STP operational mode to be changed while VLANs are associated with an STP domain. Mode change is allowed only for CIST domains.