For many years, VMware administrators depended on standard virtual switches in their vSphere virtual infrastructure....
While the standard virtual switch was useful, it was limited in scope, only capable of working with one physical host at a time. Enter the VMware vSphere Distributed Switch. Introduced as part of vSphere 4, vSphere Distributed Switch adds a much-needed layer of flexibility to VMware environments, as it connects a single virtual switch to multiple hosts in a cluster or multiple clusters. On top of this, VMware vSphere Distributed Switch helps centralize management, improves security through health monitoring and boasts multiple networking benefits.
To learn more about what VMware vSphere Distributed Switch (vDS) can do, take a look at these five quick tips.
Centralize management with switches
By now you're likely more than a little familiar with the general concept of VMware vDS and have a basic understanding of how it works. You may, however, still be wondering why you should choose to implement vDS over a standard virtual switch -- after all, vSphere Standard Switch (vSS) satisfies the needs of most administrators. However, if you're looking for a more centralized form of management, especially in vCenter, it might be time to make the switch to the vDS approach.
So what makes vDS a better option from a management perspective than vSS? For starters, vDS can monitor the network configuration of each ESXi host associated with the switch. VDS also provides an added level of security in the event that vCenter goes down, as each vSphere host stores -- and regularly updates -- a cached copy of vDS configuration. In the event that vCenter fails, the host can continue to use this cached copy, preventing significant downtime and giving you piece of mind.
Networking benefits of VMware vDS
The benefits of using vDS aren't limited to creating a more centralized form of management; vDS resolves a lot of common networking issues, too. One of the main issues with networking in the data center is that networks are resistant to change and require manual intervention when problems arise. The vSphere Standard Switch attempted to clear up this issue by providing programmatic control over networking organization on individual ESXi hosts, but this method has problems of its own. Since vSS instances exist on each ESXi host, admins must configure and monitor them on a host-by-host basis, allowing for a greater margin of error. VDS eliminates this issue by using a software-based mechanism to aggregate vSS deployments. In addition to this, vDS includes a number of other features to improve network performance, such as traffic filtering and network I/O control.
Given the additional features and capabilities that VMware vDS offers, one might wonder why anyone would choose to use vSS over vDS. The answer is surprisingly simple: to save money. VSphere Standard Switch is included in every version of vSphere, whereas vDS can only be accessed by purchasing the vSphere Enterprise Plus edition, VMware's most expensive licensing plan. While the higher price tag comes with perks, including NetFlow support, health monitoring and port mirroring, it also makes vDS cost-prohibitive for many customers. Fortunately, vSS already offers a number of powerful features that have helped maintain its popularity with customers over the years.
VSphere 6 and vDS
With the release of vSphere versions 5 and 6 came a number of new features and updates to preexisting ones, including VMware networking tools. For example, vSphere 5 introduced support for port mirroring for VMware vDS, as well as the addition of link layer discovery protocol. The former allows for a network switch to send copies of traffic from one switch port to another, while the latter offers detailed information about network devices. VSphere 6 brought even more improvements to vDS. New features such as network I/O control help create vDS quality of service, and multicast snooping boosts scalability and performance. With networking becoming more a focal point for VMware, it's likely that we'll see continued improvements to vDS in future releases of vSphere.
Test your vDS knowledge
You've learned what the VMware vSphere Distributed Switch is, what it's capable of, when to use it and how it's being improved -- what's next? Before implementing VMware vDS in your virtual environment, consider taking a short quiz to see how well you understand virtual switches, including vDS. Once you're absolutely certain of your vDS prowess, go forth and prosper in all of your networking endeavors.
How to upgrade vDS to vSphere 6
Explore VMware vSOM and vSphere licensing changes
Create a virtual switch strategy for your network