Spanning Tree Protocol has always been a problem with Mac OS X Server. This goes back to the early days when OS’s whacked each other over the head with rocks to go from Alpha to Beta. This usually manifests itself in weird speed and connectivity issues. You can mitigate by changing timing values, but when testing, it is often easiest to start by disabling Spanning Tree Protocol, seeing if the problems you have go away and then working from there.
By default, Spanning Tree is enabled on all Cisco Switches. In this article we’ll look at disabling Spanning Tree Protocol. But it is important to point out that once disabled, it is important to keep in mind that creating an additional VLAN automatically runs another instance of spanning tree protocol, so you may need to repeat this process in the future.
First backup the device. Then, ssh into the device:
You should be prompted for credentials at this time if using telnet. If you are using SSH you should only be prompted for the password. Once connected to the device you will need to go into enable mode by typing en at the command prompt and hit enter:
It may prompt you for a password, which you will need to know. Once complete you will notice that the prompt turns from an > to an # symbol. Now that you have administrative access, you will need to go into global configuration mode using the config t command:
Now let’s actually disable spanning tree protocol. Enter in the no verb followed by spanning-tree, the protocol we’re disabling, followed by VLAN, followed by the VLAN identifier:
no spanning-tree VLAN vlan-id
Repeat for each VLAN if you need to do this on multiple. When done, exit config mode by entering the end command:
You can then enter the show command along with the spanning-tree option and view to see if there are any remaining spanning tree’s still active and verify if your command took:
If the command took and spanning tree is no longer enabled. Run the coppy command, followed by running-config and then startup-config, which copies your running configuration to your startup configuration making your change permanent:
copy running-config startup-config
It is then usually recommended to go ahead and reboot servers and clients prior to testing.