Spanning tree Port Type Question

[William Scott]

Hello,

I was curious if I have a Nexus 5k switch which has the port configured for spanning-tree port type normal, connected via an uplink to a Nexus 7k and on the 7k there is no spanning-tree port type configured, can I configure this 7k side as a trunk without impacting the status of the link?  Will this result in any issues or is this a proper way of configuring the devices?

[Reza Sharifi]

Hi,

Connecting the 5k to a 7k using a trunk port should not be an issue. 

Configuring Spanning Tree Network Ports on Specified Interfaces

You can configure spanning tree network ports on specified interfaces.

Bridge Assurance runs only on spanning tree network ports.

This command has three states:

• spanning-tree port type network —This command explicitly configures the port as a network port. If you enable Bridge Assurance globally, it automatically runs on a spanning tree network port.
• spanning-tree port type normal —This command explicitly configures the port as a normal spanning tree port and Bridge Assurance cannot run on this interface.
• no spanning-tree port type —This command implicitly enables the port as a spanning tree network port if you define the spanning-tree port type network default command in global configuration mode. If you enable Bridge Assurance globally, it automatically runs on this port.
• link
• https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/configuration/guide/cli/CLIConfigurationGuide/SpanningEnhanced.html#25903
• HTH

[William Scott]

Hello Reza, so there should be no issue with configuring the 7k side of the interface as a spanning-tree port type trunk?

[Reza Sharifi]

Hi Scott,

Since you are connecting 2 switches together, it should be network.

spanning-tree port type network

The options are edge, network and normal.

HTH

[William Scott]

Should it be "network" on both the 7k and the 5k or can the 7k be set to network and the 5k set to normal?

One other question I have is for the 7k if an interface is connected to a F5 LTM Global Load Balancer, which mode should this be set to?

[balaji.bandi]

• Depends on the design you building, is this enhanced vPC ? look at the below guide.

https://www.cisco.com/c/dam/en/us/products/collateral/switches/nexus-7000-series-switches/C07-572834-00_STDG_NX-OS_vPC_DG.pdf

[balaji.bandi]

anything connected to end device it should be edge.

[Reza Sharifi]

Should it be "network" on both the 7k and the 5k or can the 7k be set to network and the 5k set to normal?

Should be the same (networks) on both sides since you are connecting 2 switches together.

As for the F5 LTM, it should be trunk port. See this document. If you are not using a Portchannel to aggregate multiple links as in the document, you simply configure one link.

https://support.f5.com/csp/article/K13142#vPC

HTH