11-03-2021 11:45 AM - edited 02-01-2024 12:28 PM
Hey all,
I wanted to take a moment to look at spanning tree. By default, ICX switches run 802.1d spanning tree on a per-vlan basis. Ideally, we want to use a protocol with faster convergence such as rapid spanning tree (802.1w). I will go through some general configuration steps and a few best practices. These configurations will not suit all customers, but it is a good starting point for many.
Enabling RSTP on vlan(s)
ICX#conf t
ICX(config)#vlan 10 20 30 <--edits three vlans at once. You can edit vlans one at a time or using a range via the 'to' syntax (vlan 1 to 20)
ICX(config-mvlan-10*30)#spanning-tree 802-1w
Now that 802.1w is running, we will want to set a root bridge priority. If no priority is defined, the default of 32768 will be used. Let us assume you want this switch to be the root bridge. A lower priority number wins, so let us go ahead and set it to zero to ensure this switch becomes root bridge:
ICX(config-mvlan-10*30)#spanning-tree 802-1w priority 0
The resulting configuration will look like this:
vlan 10 by port
tagged ethe 1/1/1 to 1/1/48 ethe 1/2/1 ethe 1/2/2 ethe 1/2/3 ethe 1/2/4 ethe 1/2/5 ethe 1/2/6 ethe 1/2/7 ethe 1/2/8
spanning-tree 802-1w
spanning-tree 802-1w priority 0
!
vlan 20 by port
tagged ethe 1/1/1 to 1/1/48 ethe 1/2/1 ethe 1/2/2 ethe 1/2/3 ethe 1/2/4 ethe 1/2/5 ethe 1/2/6 ethe 1/2/7 ethe 1/2/8
spanning-tree 802-1w
spanning-tree 802-1w priority 0
!
vlan 30 by port
tagged ethe 1/1/1 to 1/1/48 ethe 1/2/1 ethe 1/2/2 ethe 1/2/3 ethe 1/2/4 ethe 1/2/5 ethe 1/2/6 ethe 1/2/7 ethe 1/2/8
spanning-tree 802-1w
spanning-tree 802-1w priority 0
Now that our RSTP instances are running, let's take a look at a couple best practices.
Switch-to-switch connections should be defined as point-to-point links to optimize convergence times. In this example, let us assume ports 1/2/1 through 1/2/8 are all switch-to-switch links:
ICX#conf t
ICX(config)#interface ethernet 1/2/1 to 1/2/8
ICX(config-mif-1/2/1-1/2/8)#spanning-tree 802-1w admin-pt2pt-mac
The resulting configuration:
interface ethernet 1/2/1
port-name Switch-to-Switch-Connection
spanning-tree 802-1w admin-pt2pt-mac
Switch-to-client (edge) connections should be defined as operational edge ports. In this example, let us assume ports 1/1/1 through 1/1/48 are all client edge ports:
ICX#conf t
ICX(config)#interface ethernet 1/1/1 to 1/1/48
ICX(config-mif-1/1/1-1/1/48)#spanning-tree 802-1w admin-edge-port
Client ports can also have STP BPDU Guard enabled. This will shut down the port if any BPDUs are received on the port.
ICX#conf t
ICX(config)#interface ethernet 1/1/1 to 1/1/48
ICX(config)#stp-bpdu-guard
The resulting configuration:
interface ethernet 1/1/1
port-name Client-Port
spanning-tree 802-1w admin-edge-port
stp-bpdu-guard
To see RSTP information, you can use the following commands:
ICX#show 802-1w
ICX#show 802-1w detail
Note: If you are running 802.1d, you will use 'show spanning-tree' and 'show spanning-tree detail'. MSTP also has unique commands such as 'show mstp' and 'show mstp detail'
To see all available configuration options for spanning tree, please see our FastIron Layer 2 Switching Configuration Guide:
Let us know if you have any questions!
11-07-2021 10:45 PM
Great starting point for RSTP deployment. Thank you.
11-09-2021 05:04 AM
Dear Ben Beck,
Good one, it would be great if you could share some troubleshooting steps to resolve any STP Loop.
Thank you for sharing this!!!
Regards,
Abilash PR.
10-29-2023 12:07 PM
Hi Ben,
Whats the difference between configuring pt2pt stp configuration on interface as opposed to applying it on vlan instead? I am new to Ruckus switching and wanting to uplink to an extreme switch using RSTP. When I enable RSTP I am getting constant BPDU errors on the extreme switch port. If I apply below to interface will it stop the errors ?
spanning-tree 802-1w admin-pt2pt-mac
01-31-2024 09:43 AM
Thank you for this! Which option would you use for a switch to AP with clients needing vlan 20 and 30? Also, the Mesh APs that have a switch connected?