Spanning Tree Protocol (STP) Configuration for Araknis 220/320/420 Series Switches

Follow these instructions to configure STP on your switch. If you're experiencing connectivity issues, read Troubleshooting Spanning Tree (STP) connection issues.

Note: You must configure STP globally and for each port on the switch.

Global Settings

Navigate to Settings > STP.
Click the Global Settings tab > STP tab.
Set the STP State to Enabled.
Set Force Version to RSTP, then click Apply.
Go to the RSTP Port Settings tab.
Click the check box at the top of the table to select all the items.
Click the Edit button at the top right of the page.
Set Auto Edge to No.
Set Edge Port Conf/Oper to No.
Set Port Status to Enabled.
Click Apply.

Root Bridge Settings

Return to the Global Settings > STP tab.
Configure the switch Priority based on where the switch is in the network topology. Read STP topology best practices Understanding Spanning Tree Protocol (STP) & Best Practices for more information.
- If it is the core switch, set the priority to 4096.
- If it is an edge switch, select the priority value for the switch tier.

Troubleshooting Spanning Tree (STP) connection issues

Look at the Root Address and Bridge Address values in the core switch.

Root Address is the MAC address of the currently elected root bridge device.
Bridge Address is the MAC address of the switch you're currently logged in to.

These should match in the core switch. If they do not, log in to the switch acting as the Bridge Address and adjust the Bridge Priority.

Specific devices falling offline

If a specific device is falling offline, check the logs to see if the port state is continuously switching between Up and Down. This is also known as flapping.

To resolve the issue, enable Edge Port on that specific switchport and notate it in the project notes.

Caution: Disable Edge Port if you change the connected device on the switchport. Failure to do so may cause a switching loop.