STRIDE SE-MC2U-SC, User Manual

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VLAN with RSTP
Extra care must be taken when enabling both VLANs and redundancy, or communications
failures may occur.
The example shown in the following diagram depicts the problem with running the Rapid
Spanning Tree Protocol (RSTP) and VLANs at the same time. The IEEE 802.1D based
RSTP is not aware of the VLAN configuration. Therefore, in the example, one of the
Network Ports for VLAN 3 is being blocked (see VLAN Port Settings topic in this section
about Network type ports). This prevents VLAN 3 from being able to forward data to all its
members.
Blocked by
RSTP
Tag
ged
for
VLA
N 3
Tag
ged
fo
r V
LA
N
3
Tagge
d for
VL
AN
2
Ta
gg
ed
fo
r V
LAN
1
Switch
Switch
Ethernet
Device
Ethernet
Device
VLAN
1
Switch
Ethernet
Device
Ethernet
Device
VLAN
2
Switch
Ethernet
Device
Ethernet
Device
Ethernet
Device
Ethernet
Device
VLAN
3
4-44
Chapter 4 - Managed Switch Software Setup
Stride Industrial Ethernet Switches User Manual 2nd Ed. Rev. A