Support for Differentiated Services Code Point (DSCP) in VMware vSphere

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

This article provides information on support for Differentiated Services Code Point (DSCP) in vSphere.

DSCP is a field in the IPv4/IPv6 header, which is used to implement networking QoS. For more information on DSCP, see RFC 2474.

Resolution

The DSCP tag feature is supported starting with vSphere Distributed Switch (vDS) 5.5 and later. For more information, see the Mark Traffic on a Distributed Port Group or Uplink Port Group section of the vSphere Networking Guide.

Note: This is introduced as Traffic Filtering and Marking and can only be configured using the VMware vSphere Web Client. For more information, see the Traffic Filtering and Marking Policy section in the vSphere Networking Guide.

Additional Information

DSCP tagging is done as part of L3 QoS on switch.

Starting with vSphere 5.5, the DSCP marking support enables users to insert tags in the IP header. IP headerlevel tagging helps in Layer 3 environments, where physical routers function better with an IP header tag than with an Ethernet header tag.

ACLs allow you to create fine grain control of what traffic is allowed in or out of a virtual machine, set of virtual machines or an entire port group. The feature is configured at the port group level and allows for an unlimited number of rules. The rules are processed in the VMkernel, meaning no external appliance is needed which equates to no single point of failure and faster processing of rules and in some cases reduced network traffic as rule processing happens before the traffic leaves the ESXi host. For more information, see VMware vSphere Blog.