10 VMware vSwitch Configuration Best Practices

The VMware vSwitch is a central component of the VMware vSphere virtualization platform. It is responsible for connecting virtual machines to the physical network.

Configuring the vSwitch properly is essential for optimal performance and security of the virtualization environment. In this article, we will discuss 10 best practices for configuring the VMware vSwitch.

1. Use a dedicated management network

A dedicated management network ensures that your virtual machines (VMs) have uninterrupted access to the resources they need, even if the network connecting them to the outside world goes down. By keeping management traffic separate from other types of traffic, you can also more easily troubleshoot and diagnose problems.

Additionally, using a dedicated management network can improve security by making it more difficult for unauthorized users to gain access to your VMs. And finally, dedicating a network to management traffic can help improve performance by reducing congestion on other networks.

2. Disable unused ports on the vSwitch

If you leave unused ports enabled on your vSwitch, it’s possible for someone to connect to those ports and gain access to your VMware environment. By disabling unused ports, you can help prevent unauthorized access.

To disable unused ports on your vSwitch, simply go to the “Configure” tab and select the “Ports” option. From there, you can disable any ports that are not being used.

3. Configure NIC Teaming for redundancy and performance

NIC Teaming allows you to aggregate multiple physical NICs into a single logical adapter, providing increased bandwidth and redundancy. If one of the physical NICs fails, traffic is automatically rerouted through the remaining NICs.

Configuring NIC Teaming is a best practice for two main reasons:

1. Increased Bandwidth: By aggregating multiple NICs, you can increase the available bandwidth, which can be important for performance-sensitive applications.

2. Redundancy: In the event of a physical NIC failure, traffic is automatically rerouted through the remaining NICs, ensuring that your applications remain up and running.

4. Enable Jumbo Frames to increase throughput

Jumbo Frames are larger than the standard Ethernet frame size of 1,500 bytes. By increasing the frame size, you can increase the amount of data that can be sent in a single frame. This results in fewer frames being sent, which reduces overhead and increases throughput.

To enable Jumbo Frames on a vSwitch, simply navigate to the vSwitch properties in the vSphere Web Client and select the “Edit” button. From there, select the “Teaming and Traffic Shaping” tab and check the “Enable Jumbo Frames” box.

5. Isolate traffic types using VLANs

When you have different types of traffic on the same network, they can interfere with each other and cause problems. For example, if you have video traffic and data traffic on the same network, the video might start to stutter or freeze because the data is taking up too much bandwidth.

Isolating traffic types using VLANs prevents this from happening because it keeps the different types of traffic separate. That way, each type of traffic can use as much bandwidth as it needs without affecting the other types.

To set up VLANs in VMware vSwitch, you’ll need to create a new virtual switch and then add the VLANs you want to isolate. You can do this in the “Edit Settings” dialog for the virtual switch.

6. Implement Private VLANs (PVLAN) for additional isolation

PVLANs provide an extra layer of security and isolation by creating separate broadcast domains within a single VLAN. This means that each host on a PVLAN can only communicate with a limited set of other hosts, which reduces the risk of accidental or malicious traffic between hosts.

PVLANs also make it easier to control traffic flow between virtual machines (VMs) because you can configure them to allow or deny specific types of traffic. For example, you could allow VM-to-VM traffic but block all traffic from the outside world.

Configuring PVLANs can be a bit complex, so it’s important to understand how they work before you start. However, the extra security and isolation they provide is well worth the effort.

7. Use Port Groups for security, monitoring and administration

Port groups allow you to logically segment your network into different segments, each with its own security policies, monitoring settings and administrative controls. This allows you to better control traffic flow between virtual machines and helps to prevent accidental or unauthorized communication between VMs.

Additionally, port groups can be used to monitor traffic statistics and performance data for individual VMs or groups of VMs. This information can be invaluable in troubleshooting networking issues or identifying potential bottlenecks.

Finally, port groups make it easier to manage and administer your VMware vSwitch by allowing you to apply changes to a group of VMs rather than individually. This can save a lot of time and effort when making changes to your vSwitch configuration.

8. Utilize Network I/O Control for resource allocation

When you have multiple virtual machines running on a single host, they are all sharing the same physical network interface card (NIC). This can lead to contention for resources, and if not properly configured, can result in decreased performance for your applications.

Network I/O Control allows you to allocate specific amounts of bandwidth to each virtual machine, ensuring that they have the resources they need to function properly. This is especially important if you have latency-sensitive applications, such as VoIP or video conferencing, running on your VMs.

To configure Network I/O Control, go to the “Configuration” tab in vSphere Web Client, select “Network I/O Control,” and then click “Edit.” From here, you can specify the amount of bandwidth that each VM can use.

9. Monitor your environment with NetFlow

NetFlow is a feature that was introduced in VMware vSphere 4.1 that allows you to collect network traffic data and monitor the performance of your virtual infrastructure. NetFlow data can be used to troubleshoot networking issues, identify bandwidth bottlenecks, and track which applications are using the most bandwidth.

Configuring NetFlow on your vSwitches is a simple process, and there are many NetFlow collectors available that can help you make sense of the data. Once you have NetFlow data, you can use it to create custom reports and dashboards that will help you keep an eye on your environment and ensure that it is running smoothly.

10. Minimize latency by configuring QoS

When you have multiple virtual machines running on a single host, they are all sharing the same physical network interface. This can lead to contention and increased latency if not properly configured.

By configuring QoS, you can give each virtual machine a guaranteed minimum amount of bandwidth, which will help to reduce latency and improve performance.