Spanning Tree Operation With Switch Meshing - HP ProCurve 5300xl Series Management Manual

Switch Meshing
Operating Notes for Switch Meshing
7-20

Spanning Tree Operation with Switch Meshing

Using STP or RSTP with several switches and no switch meshing configured
can result in unnecessarily blocking links and reducing available bandwidth.
For example:
Problem:
STP enabled and creating
traffic bottlenecks.
Server
Server
Switch Switch
Switch
Switch
Switch Switch
=
Figure 7-17. Example Using STP Without and With Switch Meshing
If you enable STP, RSTP, or MSTP on any meshed switch, you should enable
the same spanning-tree protocol on all switches in the mesh. (That is, if you
are going to use spanning-tree in a switch mesh, all switches in the mesh
should be configured with the same type of spanning-tree: 802.1d/STP, 802.1w/
RSTP, or 802.1s/MSTP.) Spanning-Tree interprets a meshed domain as a single
link. However, on edge switches in the domain, STP and RSTP will manage
non-meshed redundant links from other devices. For example:
Solution:
Enabling meshing on links between
switch ports removes STP blocks on
meshed redundant links.
Server
Switch
Mesh
Domain
Meshed
Switch
Meshed
Switch
Switch
STP, RSTP, or MSTP Blocking a Redundant Link
Server
Meshed
Switch
Meshed
Switch
Switch