Which Nexus is primary

[fsebera]

Normally when you wanted to see which Nexus was primary, you could just run the show vpc role command and the output would clearly state vPC role is primary or vPC role secondary - simple.

Now the output states primary, operational secondary.

My question - Based on the sh vpc role below, is this the primary or secondary?

My other question - is there more to this story and this is why primary, operational secondary is shown?

Thanks

Frank

N3K-A# sh vpc role

vPC Role status
----------------------------------------------------
vPC role                        : primary, operational secondary
Dual Active Detection Status    : 0
vPC system-mac                  : 00:23:04:xx:xx:xx
vPC system-priority             : 8000
vPC local system-mac            : 7c:69:f6:cc:dd:ee
vPC local role-priority         : 32667

[Reza Sharifi]

Frank,

N3K-A is primary.

If you go the other device and issue the same command, you should see it showing as secondary.

vPC role                          : secondary

When the two vPC systems are joined to form a vPC domain, the priority decides which device is the vPC primary and which is the vPC secondary. If the primary device were to reload, when the system comes back online and connectivity to the vPC secondary device (now the operational primary) is restored, the operational role of the secondary device (operational primary) will not change, to avoid unnecessary disruptions. This behavior is achieved with a sticky-bit method, whereby the sticky information is not saved in the startup configuration, thus making the device that is up and running win over the reloaded device. Hence, the vPC primary becomes the vPC operational secondary.

Link:

http://www.cisco.com/c/en/us/products/collateral/switches/nexus-5000-series-switches/design_guide_c07-625857.html

HTH

[fsebera]

Secondary, operational primary and now I understand why it states primary and secondary on the same line.

Thanks

Frank

N3K-B# sh vpc role

vPC Role status
----------------------------------------------------
vPC role                        : secondary, operational primary
Dual Active Detection Status    : 0
vPC system-mac                  : 00:23:04:ee:be:6e
vPC system-priority             : 8000
vPC local system-mac            : a4:4c:11:2d:70:01
vPC local role-priority         : 32667

[Austin Sabio · Accepted solution]

It means its configured primary but it's now operating secondary. Once a vPC system reloads then it will operate primary. 

Primary and Secondary vPC Roles

"In a vPC system, one vPC switch is defined as primary and one is defined as secondary, based on defined priorities. The lower number has higher priority, so it wins. Also, these roles are nonpreemptive, so a device may be operationally primary, but secondary from a configuration perspective.

To understand the operational role of a vPC member, you need to consider the status of the peer-keepalive link and the peer link.

When the two vPC systems are joined to form a vPC domain, the priority decides which device is the vPC primary and which is the vPC secondary. If the primary device were to reload, when the system comes back online and connectivity to the vPC secondary device (now the operational primary) is restored, the operational role of the secondary device (operational primary) will not change, to avoid unnecessary disruptions. This behavior is achieved with a sticky-bit method, whereby the sticky information is not saved in the startup configuration, thus making the device that is up and running win over the reloaded device. Hence, the vPC primary becomes the vPC operational secondary.

If the peer link is disconnected but the vPC peers are still connected through the vPC peer keepalive link, the vPC operational roles stay unchanged.

If both the peer link and peer-keepalive link are disconnected, both vPC peers become operational primary, but upon reconnection of the peer-keepalive link and the peer link, the vPC secondary device (operational primary) keeps the primary role, and the vPC primary becomes the operational secondary device."

http://www.cisco.com/c/en/us/products/collateral/switches/nexus-5000-series-switches/design_guide_c07-625857.html

Please rate, if helpful. 

Thank you.

[fsebera]

Ahhhhh, and that makes sense as we just reloaded the primary.

THANK YOU

Frank