Dcict - 640-916-1.9A

Front 1

What advantage do vPC's have over traditional Etherchannel links (3 bullets)?

Back 1

-vPC's allow single virtual uplink to a pair of upstream devices.
-The upstream devices are seen as a single logical switch, even though they are not. -Traffic can be load-balanced across multiple physical links to the upstream devices.

Front 2

What are vPC Peers?

Back 2

They are a pair of Nexus devices that will act as a single logical switch for downstream device.

Front 3

What does the vPC Peer Link provide (10 bullets)?

Back 3

-It will create the illusion of a single logical control plane.
-It will forward BPDU's and LACP packets.
-It will enable the devices to establish and maintain a primary/secondary relationship.
-MAC tables will be synchronised across the Peer Link.
-IGMP entries (for IGMP snooping) will be synchronised across the Peer Link.
-It will transmit multicast traffic.
-It will transmit traffic from Orphan Ports.
-Will provide HSRP transmission.
-It will transmit Cisco Fabric Services (CFS) traffic.
-Unicast traffic may be carried under certain failure conditions.

Front 4

What is Cisco Fabric Services (CFS) used for?

Back 4

This provides all the Sync technologies that enable vPC to work.

Front 5

What is the Peer Keepalive Link used for (3 bullets)?

Back 5

-This is a backup link to test the status of the vPC peers using keepalives.
-Keepalive messages are not sent over the Peer Link.
-Data or Sync messages will not be sent over the Peer Keepalive Link.

Front 6

If a N5K uplinks to a pair of N7K's, describe the config at each end of the link (2 bullets).

Back 6

-vPC will be configured on the N7K's.
-Normal Etherchannel will be configured on the N5K.

Front 7

What is a vPC Member Port?

Back 7

It is a port that is part of the vPC on one of the VPC Peers.

Front 8

What is an Orphan Port?

Back 8

It is a port that connects to another device but is not participating in the vPC.

Front 9

What is a vPC domain (2 bullets)?

Back 9

-All the components that make up the vPC config on a pair of vPC peers.
-A vPC Domain requires a numeric identifier known as a Domain ID.

Front 10

Name 2 limitations of vPC.

Back 10

-The Peer Link must use at least 1 x 10G port, 2 are recommended.
-vPC cannot be configured across VDC's.

Front 11

At what layer does vPC operate.

Back 11

L2, although L3 features such as HSRP can be used in conjunction with vPC.

Front 12

Describe an example of dual-sided vPC.

Back 12

If a pair of N7K's were providing a vPC domain to a pair of N5K's, which were in turn providing a vPC domain to a pair of N2K's, this would be a dual-sided vPC configuration.

Front 13

What info will the "show vpc brief" command display (3 bullets)?

Back 13

-vPC domain and Peer status.
-vPC Peer-Link status.
-vPC status - i.e. the vPC link to the downstream switch.

Front 14

What info will the "show vpc peer-keepalive" command display (2 bullets)?

Back 14

-Peer-Keepalive Status - status, interface, age, last update.
-Peer-Keepalive Parameters - IP details, timers, UDP port, TOS.

Front 15

What info will the "show vpc role" command display (2 bullets)?

Back 15

-Role of the local switch.
-Local Role-Priority of the local switch (lower is better).

Front 16

What command could you use to check that the vPC config on two peers matches?

Back 16

-"show vpc consistency-parameters" - global.
-"show vpc consistency-parameters interface port-channel 20" - per interface.