Enabling Single Spanning Tree Protocol

Single Spanning Tree Protocol can be enabled at system or global level.

Enable SSTP only if the device contains more than one port-based VLAN and you want all the ports to be in the same STP broadcast domain. If the device has only one port-based VLAN (the default VLAN), then the device is already running a single instance of STP. In this case, you do not need to enable STP.

Enter the global configuration mode.
```
device# configure terminal
```

Configure a single spanning tree.
```
device(config)# spanning-tree single
```

Change STP bridge parameters by using the forward-delay, hello-time, max-age, and priority keywords.
```
device(config)# spanning-tree single forward-delay 4 hello-time 3 max-age 10
priority 0
```

Change global STP parameter for all the ports or for a specific port using the priority keyword.
```
device(config)# spanning-tree single priority 0
```
```
device(config)# spanning-tree single ethernet 1/1/1 priority 0
```

The following example shows how to enable SSTP for all the ports. Bridge and port parameters are configured.

device# configure terminal
device(config)# spanning-tree single
device(config)# spanning-tree single forward-delay 4 hello-time 3 max-age 10
priority 0
device(config)# spanning-tree single  priority 0

The following example shows how to enable SSTP for a specific port. Bridge and port parameters are configured.

device# configure terminal
device(config)# spanning-tree single
device(config)# spanning-tree single forward-delay 4 hello-time 3 max-age 10
priority 0
device(config)# spanning-tree single ethernet 1/1/1 priority 0