Installation manual

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SIGNAMAX LLC • www.signamax.eu
Note: The current root port and current root cost display as zero when this device is not
connected to the network.
Configuring Global Settings
Global settings apply to the entire switch.
Command Usage
• Spanning Tree Protocol
11
Uses RSTP for the internal state machine, but sends only 802.1D BPDUs. This creates
one spanning tree instance for the entire network. If multiple VLANs are implemented
on a network, the path between specific VLAN members may be inadvertently disabled
to prevent network loops, thus isolating group members. When operating multiple
VLANs, we recommend selecting the MSTP option.
• Rapid Spanning Tree Protocol
11
RSTP supports connections to either STP or RSTP nodes by monitoring the incoming
protocol messages and dynamically adjusting the type of protocol messages the RSTP
node transmits, as described below:
- STP Mode – If the switch receives an 802.1D BPDU (i.e., STP BPDU) after a port’s
migration delay timer expires, the switch assumes it is connected to an 802.1D bridge
and starts using only 802.1D BPDUs.
- RSTP Mode – If RSTP is using 802.1D BPDUs on a port and receives an RSTP BPDU
after the migration delay expires, RSTP restarts the migration delay timer and begins
using RSTP BPDUs on that port.
• Multiple Spanning Tree Protocol
MSTP generates a unique spanning tree for each instance. This provides multiple
pathways across the network, thereby balancing the traffic load, preventing wide-scale
disruption when a bridge node in a single instance fails, and allowing for faster
convergence of a new topology for the failed instance.
- To allow multiple spanning trees to operate over the network, you must configure a
related set of bridges with the same MSTP configuration, allowing them to participate
in a specific set of spanning tree instances.
- A spanning tree instance can exist only on bridges that have compatible VLAN
instance assignments.
- Be careful when switching between spanning tree modes. Changing modes stops all
spanning-tree instances for the previous mode and restarts the system in the new
mode, temporarily disrupting user traffic.
Command Attributes
Basic Configuration of Global Settings
• Spanning Tree State – Enables/disables STA on this switch. (Default: Enabled)
• Spanning Tree Type – Specifies the type of spanning tree used on this switch:
11. STP and RSTP BPDUs are transmitted as untagged frames, and will cross any VLAN boundaries.