Introduction to VDC Part 1

Introduction to VDC

--> VDC stands for Virtual Device Contexts.

--> By using VDC we can divide one physical Nexus Switch into one or more logical nexus switches.

--> VDCs are similar to Context in ASA or SDR in IOS XR.

VDC Advantages

1) Can provide managed services to customers

2) improved security

3) separate administrative plane and fault isolation.

How VDC is different from VRF and VLAN

VLAN:

--> Divides one broadcast domain into multiple broadcast domains.

--> Provides only separate layer 2 data plane.

--> Same Management Plane and Control Plane.

VRF:

--> Divides one Router into multiple logical Routers.

--> Provides Separate Layer 3 Data Plane and Control Plane.

--> Same Management Plane for all the logical Routers.

VDC: 

--> Divides one physical Nexus Switch into one or more logical nexus switches.

--> Separate Layer 3 Management Data Plane, Control Plane and Data Plane for all the VDC.

Types of VDC

1) Default VDC

--> When you first login into Nexus 7K Switch, you are in Default VDC.

--> Default VDC is created by NXOS on bootup.

--> VDC1 is the default VDC.

--> Any interface can be assigned to default VDC and it can forward the traffic similar to the non-default VDC.

--> We can Perform following tasks can be done in default VDC such as,

i) Creation/updation/deletion of VDC

ii) Allocation of Resources such as Interfaces, memory

iii) Control Plane Policing

iv) NX-OS Upgrade across all VDC

2) ADMIN VDC

--> Admin VDC can be created from the initial configuration wizard.

--> Admin VDC is also used for managing the other VDCs.

--> Default VDC is replaced with ADMIN VDC on SUP2/SUP2E with the Cisco NX-OS 6.1

--> Only Management interface can be assigned to Admin VDC.

--> You can create Admin VDC in two ways,

1) Execute the command system admin-vdc after booting of Nexus OS. In this scenario, Default VDC becomes Admin VDC.

2) Execute the command system admin-vdc migrate new-vdc name. All the configurations from Default VDC migrated to New VDC.

--> When you enable ADMIN VDC it replaces the default VDC in Nexus Switch.

--> Default and admin VDC cannot be present at the same time in Nexus Switch.

--> ADMIN VDC cannot handle user traffic similar to Default VDC.

Non Default VDC

--> Non Default VDC can be created from Default VDC or Admin VDC.

--> Changes made to Non Default VDC does not affect other VDCs.

--> Each VDC is having its own stored configuration file.

--> Non Default VDC is used for handling the user traffic as interfaces can be allocated to it.

Storage VDC

--> Storage VDC is used when we need to implement SAN functions on Nexus Switch.

--> Storage VDC is counted against the number of VDC license on Nexus Switch.

--> We can assign two different types of interfaces to storage VDC: i) FCOE Interface ii) Shared Interface

No.of VDCs supported by Nexus Switch

--> The maximum number of VDCs supported by Nexus Switch depends upon the Supervisor it is using.

--> If Nexus 7K is using SUP1 engine then we can create upto 4 VDC + 1 Admin VDC.

--> If Nexus 7K is using SUP2 engine then we can create upto 4 VDC + 1 Admin VDC.

--> If Nexus 7K is using SUP2E engine then we can create upto 8 VDC + 1 Admin VDC.

VDC Requirements

--> To create VDCs, an advanced license is required on Nexus Switch.

--> The license is associated with the serial number of a Cisco Nexus 7000 switch chassis.

--> The storage VDC is enabled using the storage license associated with a specific line card.

--> You can try the feature for the 120-day grace period. When the grace period expires, any nondefault VDCs will be removed from the switch configuration.

Nexus Switches that support VDC

--> Nexus 5K(NO)

--> Nexus 7K(Yes)

--> Nexus 9K(NO)

Ref: Cisco.com

Md.Kareemoddin

CCIE # 54759