The color coding of each node and link corresponds to its state. The colors and what they indicate are described in the following list:

• Green: Indicates that the element is in good health and functioning as intended.

• Yellow: Indicates that the element is in warning state and requires attention to prevent any further problems.

• Red: Indicates that the element is in critical state and requires immediate attention.

• Gray: Indicates lack of information to identify the element or the element has been discovered.

  Note

  In the Topology window, FEX appears in gray (Unknown or n/a) because health is not calculated for FEX. After moving a cable from one port to another port, the old fabric link is retained in the Topology window, and it is shown in the red color indicating that the link is down. The port movements are not updated in the Topology window. You need to rediscover the switch for the updated ports to be displayed in DCNM.

• Black: Indicates that the element is down.

Starting from Cisco DCNM Release 11.4(1), if a switch is in maintenance mode, a Maintenance Mode badge is displayed next to the switch. If a switch is in migration mode, a Migration Mode badge is displayed next to the switch.

You can search the topology based on the scope. The default scopes available from the SCOPE drop-down list is: DEFAULT_LAN and DEFAULT_SAN. The search options differ based on the chosen scope.

The following search options are available for DEFAULT_LAN:

• Quick Search

• VLAN

The following search options are available for DEFAULT_SAN:

• Quick Search

• VLAN

• VSAN ID/Name

When the number of nodes is large, it quickly becomes difficult to locate the intended switches and links. You can quickly find switches and links by performing a search. You are also able to search for VM tracker and generic setups. Searching feature enables you to see which leaf the host is connected to.

The following searches are available:

Note	By default, Quick Search is selected.

You can choose to view your topology based on the following options:

• Auto Refresh: Check this check box to automatically refresh the topology.

• Switch Health: Check this check box to view the switch's health status.

• FEX: Check this check box to view the Fabric Extender.

  Note	The FEX feature is available only on LAN devices. Therefore, checking this check box displays only the Cisco Nexus switches that support FEX.

  Note	If a Cisco Nexus Switch is discovered as part of SAN fabric, FEX feature is not available. FEX is also not supported on Cisco Nexus 1000V devices. Therefore, such devices will not be displayed in the topology when you check the FEX check box.

• Links: Check this check box to view links in the topology. The following options are available:

  • Errors Only: Click this radio button to view only links with errors.

  • All: Click this radio button to view all the links in the topology.

  • VPC Only: Check this check box to view only vPC peer-links and vPCs.

  • Bandwidth: Check this check box to view the color coding based on the bandwidth that is consumed by the links.

• UI controls: Check the check box to show or hide the various controls on the Topology window.

• Refresh: You can also perform a topology refresh by clicking the Refresh icon in the upper-right corner of this panel.

The topology supports different layouts along with a Save Layout option that remembers how you positioned your topology.

• Hierarchical and Hierarchical Left-Right: Provide an architectural view of your topology. Various switch roles can be defined that will draw the nodes on how you configure your CLOS topology.

  Note	When running a large-scale setup, being able to easily view all your switches on a leaf-tier can become difficult. To mitigate this, DCNM splits your leaf-tier every 16 switches.

• Random: Nodes are placed randomly on the window. DCNM tries to make a guess and intelligently place nodes that belong together in close proximity.

• Circular and Tiered-Circular: Draw nodes in a circular or concentric circular pattern.

• Custom saved layout: Nodes can be dragged around according to your preference. After you position as required, click Save to retain the positions. The next time you come to the topology, DCNM will draw the nodes based on your last saved layout positions.

Before a layout is chosen, DCNM checks if a custom layout is applied. If a custom layout is applied, DCNM uses it. If a custom layout is not applied, DCNM checks if switches exist at different tiers, and chooses the Hierarchical layout or the Hierarchical Left-Right layout. Force-directed layout is chosen if all the other layouts fail.

You can zoom in and zoom out using the controls that are provided at the bottom left of the windows or by using your mouse's wheel.

To pan, click and hold anywhere in the whitespace and drag the cursor up, down, left, or right.

To drag switches, click, hold, and move the cursor around the whitespace region of the topology.

You can click on the switch to display the configured switch name, IP address, switch model, and other summary information such as status, serial number, health, last-polled CPU utilization, and last-polled memory utilization.

From DCNM release 11.5(1), switches have only two roles, Core Router and Edge Router.

You can click a link to view the status and the port or switches that describe the link.