VMware ESX Server supports network traffic shaping with the nfshaper loadable module. A loadable packet filter module defines a filter class; multiple filter instances may be active for each loaded class. The current release supports only one filter class - nfshaper, which is a transmit filter for outbound bandwidth management that can be attached to virtual machines using either a procfs interface on the service console or the VMware Management Interface.
This section describes how to use the VMware Management Interface to attach and detach nfshaper and obtain statistics from it. It also describes how to attach, detach and query filter instances from the procfs interface on the service console.
You can view and change settings from the virtual machine details pages in the VMware Management Interface.
You must log in as root in order to change resource management settings using either the management interface or procfs.
As described in the preceding sections, you can manage network bandwidth allocation on a server from the VMware Management Interface or from the procfs interface on the service console.
The shaper implements a two-bucket composite traffic shaping algorithm. A first token bucket controls sustained average bandwidth and burstiness. A second token bucket controls peak bandwidth during bursts. Each nfshaper instance can accept parameters to control average bps, peak bps and burst size.
The procfs interface, described in Using Network Filters, is used to attach an nfshaper instance to a virtual machine, detach an nfshaper instance from a virtual machine, query the status of an nfshaper instance or issue a dynamic command to an active nfshaper instance.