20 VXLAN Interview Questions and Answers

VXLAN is a popular network virtualization technology that is used by many organizations. When applying for a position in networking or network administration, it is likely that employers will expect you to have a strong understanding and familiarity with VXLAN. Understanding what VXLAN questions you are most likely to encounter and how to properly answer them improves your chances of making a positive impression on the hiring manager. In this article, we discuss the most commonly asked VXLAN questions and how you should respond.

VXLAN Interview Questions and Answers

Here are 20 commonly asked VXLAN interview questions and answers to prepare you for your interview:

1. What is VXLAN?

VXLAN is a network virtualization technology that creates a virtual network overlay on top of an existing physical network. This overlay network allows for the creation of multiple virtual networks, each with its own unique identifier (VNI). VXLAN is often used in cloud computing and data center environments to provide greater flexibility in network design and deployment.

2. Why do we need virtual extensible LANs (VXLAN) for data centers and cloud computing?

VXLANs provide a way to create virtual LANs in a data center or cloud computing environment that are not limited by the physical constraints of a traditional LAN. With VXLANs, you can create a virtually unlimited number of LANs, each with its own unique identifier (VLAN ID). This allows you to segment traffic on a data center network in a much more flexible and scalable way than with traditional LANs.

3. Can you explain what encapsulation is in context with networks?

Encapsulation is the process of wrapping data in a layer of protection. In networking, encapsulation is used to add a header and trailer to a packet of data before it is sent over the network. The header and trailer contain information that is used by the network to route the packet to its destination.

4. What does the term “overlay network” mean?

An overlay network is a computer network that is built on top of another network. The overlay network can be used to provide additional functionality or to improve performance.

5. What are some of the main benefits of overlay networking?

Some of the main benefits of overlay networking are that it can improve network performance and resilience, and can also make it easier to scale a network. Overlay networking can also provide a way to connect disparate networks that would otherwise be unable to communicate with each other.

6. How does overlay networking work?

Overlay networking is a type of networking that allows you to create a virtual network on top of an existing network. This can be useful if you want to create a private network that is not accessible from the outside world, or if you want to create a network that is isolated from the rest of the network for security purposes.

7. Can you give me an overview of how a Virtual Extensible LAN works?

A VXLAN is a layer 2 overlay network that runs on top of a physical IP network. It uses MAC-in-UDP encapsulation to allow for a larger number of logical networks, or VLANs, to be created on top of a single physical network. This can be useful for creating isolated networks for different departments or applications, for example.

8. What’s the best way to implement VXLAN on your network?

The best way to implement VXLAN on your network is to use a hardware appliance that supports the protocol. This will ensure that your network has the necessary performance and reliability for running VXLAN.

9. What makes VXLAN more scalable than VPN or MPLS protocols?

VXLAN is more scalable than VPN or MPLS protocols because it uses a 24-bit address space as opposed to the 16-bit address space used by VPNs and MPLS. This means that VXLAN can support up to 16 million unique addresses, while VPNs and MPLS can only support up to 65,536.

10. Can you explain what a tunnel endpoint identifier (TEID) is?

A tunnel endpoint identifier (TEID) is a unique identifier that is assigned to each tunnel endpoint. This identifier is used to identify the tunnel endpoint when sending and receiving data.

11. How can you use multicast to improve communication across multiple hosts?

Multicast can be used to improve communication across multiple hosts by allowing for the efficient delivery of data to multiple destinations simultaneously. By using multicast, you can avoid having to send multiple copies of the same data to each individual host, which can save both time and bandwidth.

12. What is the difference between unicast, broadcast, and multicast?

The main difference between unicast, broadcast, and multicast is the way in which information is sent. Unicast sends information from one source to one destination, while broadcast sends information from one source to all destinations. Multicast, on the other hand, sends information from one source to a group of destinations.

13. What is VTEP? How does it work?

VTEP is a software-based layer 2 tunneling protocol that is used to connect virtual machines in a virtualized network environment. It works by encapsulating layer 2 traffic in layer 3 UDP packets and then sending them over the network to the destination VTEP.

14. What are the benefits of using VXLAN over other available technologies like VLAN, OTV, and LISP?

VXLAN has a number of benefits over other available technologies. One of the main benefits is that it allows for a much larger logical network than what VLAN can provide. VXLAN also has built in security features that make it more difficult for unauthorized users to access the network. Additionally, VXLAN is designed to be more scalable than other technologies, making it a good choice for large networks.

15. What is the role of BGP-EVPN in implementing VXLAN?

BGP-EVPN is responsible for creating the virtual tunnel endpoints (VTEPs) that are used in order to connect different VXLANs. This allows for communication between VXLANs and also allows for the creation of a layer 2 overlay network.

16. What are the various layers of control plane architecture used by VXLAN?

The various layers of control plane architecture used by VXLAN are the following:

– The ingress replication layer is responsible for replicating packets that are received by the VXLAN tunnel endpoint (VTEP) to all remote VTEPs.
– The egress replication layer is responsible for replicating packets that are destined for a VXLAN tunnel to the appropriate remote VTEP.
– The flood and learn layer is responsible for replicating broadcast, unknown unicast, and multicast (BUM) traffic to all VTEPs in the VXLAN network.
– The multicast group management layer is responsible for managing the distribution of BUM traffic to the appropriate VTEPs.

17. What types of gateways can be used to deploy VXLAN?

There are three types of gateways that can be used to deploy VXLAN: hardware VTEP, software VTEP, and hybrid VTEP.

18. What type of gateway should be deployed when connecting two VXLAN enabled fabrics?

A layer 3 gateway should be deployed when connecting two VXLAN enabled fabrics. This will allow for communication between the two fabrics at the layer 3 level.

19. What is the importance of hash algorithms in VXLAN implementation?

The hash algorithm is used to calculate a hash value that is used to determine which physical server a particular VXLAN packet should be sent to. This is important because it ensures that all packets belonging to the same VXLAN are sent to the same server, which is necessary for proper routing.

20. What are the different types of hashing mechanisms that can be used with VXLAN?

There are three different types of hashing mechanisms that can be used with VXLAN: source IP, destination IP, and source and destination IP. The source IP hashing mechanism will use the source IP address of the packet to determine which VTEP to send the packet to. The destination IP hashing mechanism will use the destination IP address of the packet to determine which VTEP to send the packet to. The source and destination IP hashing mechanism will use both the source and destination IP addresses of the packet to determine which VTEP to send the packet to.