Siemens S223 - Manual (Page 211)

User Manual UMN:CLI
SURPASS hiD 6615 S223/S323 R1.5
A50010-Y3-C150-2-7619 211
In CST, A and B are the switches operating with STP and C, D and, E are those operating
with MSTP. First, in CST, CIST is established to decide CST Root. After CST root is de-
cided, the closest switch to CST root is decided as IST root of the region. Here, CST root
in IST is IST root.
Legacy 802.1d
CST Root & IST Root
Switch A
Switch D
Switch C
Switch E
Instance 2
Instance 3
Instance 2 Instance 1
Region B (IST)
IST Root
CST
Switch B
IST Root
Region A (IST)
Region C (IST)
Fig. 8.23 CST and IST of MSTP (2)
In above situation, if B operates with MSTP, B will send it’s BPDU to CST root and IST
root in order to request itself to be CST root. However, if any BPDU having higher priority
than that of B is sent, B cannot be CST root.
For the hiD 6615 S223/S323, the commands configuring MSTP are also used to config-
ure STP and RSTP.
8.3.4 Configuring STP/RSTP/MSTP/PVSTP/PVRSTP Mode (Required)
First of all, you need to configure force-version to decide the mode before STP is config-
ured. To decide force-version of the switch, use the following command.
Command Mode Description
stp force-version {stp | rstp |
mstp | pvstp | pvrstp}
Bridge Configures Force-version in the bridge.
To delete STP configuration from the switch, use the following command.
Command Mode Description
no stp force-version Bridge Removes force-version configuration.