Nexus 9K as a Root Bridge

[Zeeshan Anwar]

I want to setup Nexus 9K as my Root-Bridge.The issue is I also have 5 Ks connected to those 9k's and each 5K's have Fabric -path Feature Enable.I Read in some documentation Fabric-Path should always be a root-Bridge for other Switches.Is there anyway that i can make my 9 ks as a Core Switch.

Attach is the config for both 9ks and 5Ks.

[Mark Malone]

Hi

I think that's a limitation with L2G-STP reading the doc below , I don't see any issue with your 9ks being the core stp root

http://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/mkt_ops_guides/513_n1_1/n5k_ops_fabricpath.html

Guidelines and Limitations of FabricPath

FabricPath has the following configuration guidelines and limitations:

•An in-service software upgrade (ISSU) is supported when the Cisco Nexus 5500 Series device is in Layer 2 mode running FabricPath and/or a vPC. The edge device that is undergoing and ISSU is in both the CE and FabricPath cloud. The same rules that are applicable in an ISSU environment on the Cisco Nexus 5500 Series device are applied in a FabricPath design.

•The spanning-tree configuration cannot have any designated port, with the exception of ports that are configured as a spanning-tree port-type edge with bridge protocol data unit (BPDU) Filtering. Bridge assurance must be disabled on all ports except on the peerlink where it is possible to keep bridge assurance enabled. Bridge assurance operates only when a port is configured as a spanning-tree port type network. Ports that are configured as default or normal ports do not run bridge assurance.

•The Cisco Nexus 5000 Series device cannot be the STP root bridge or have any designated nonedge ports in the STP topology.

•The Cisco Nexus 5000 Series device and the Cisco Nexus 2000 Fabric Extenders that are undergoing an ISSU must be a leaf on the spanning tree.

[Zeeshan Anwar]

Hi

Thanks for the reply.Just to brief again my 9Ks are acting as non rootwhere as 5ks acting as root bridge. I want my 9ks as root and 5ks as non root.

[Mark Malone]

Yes exactly there is no reason why your 9ks cannot be the root bridge there no limitation in place saying it shouldn't be set like that just because the 5ks are in fabric , its saying in that doc your 5ks shouldn't be the core so it probably best you change it to the 9ks anyway reading that

Your most powerful and central core switches should always be set as the root unless there is a specific reason not too , which I cannot see in the docs