Network resource pools determine the bandwidth that different network traffic types are given on a vSphere distributed switch.
When network I/O control is enabled, distributed switch traffic is divided into the following predefined network resource pools: Fault Tolerance traffic, iSCSI traffic, vMotion traffic, management traffic, vSphere Replication (VR) traffic, NFS traffic, and virtual machine traffic.
You can also create custom network resource pools for virtual machine traffic. You can control the bandwidth each network resource pool is given by setting the physical adapter shares and host limit for each network resource pool.
The physical adapter shares assigned to a network resource pool determine the share of the total available bandwidth guaranteed to the traffic associated with that network resource pool. The share of transmit bandwidth available to a network resource pool is determined by the network resource pool's shares and what other network resource pools are actively transmitting. For example, if you set your FT traffic and iSCSI traffic resource pools to 100 shares, while each of the other resource pools is set to 50 shares, the FT traffic and iSCSI traffic resource pools each receive 25% of the available bandwidth. The remaining resource pools each receive 12.5% of the available bandwidth. These shares apply only when the physical adapter is saturated.
The iSCSI traffic resource pool shares do not apply to iSCSI traffic on a dependent hardware iSCSI adapter.
The host limit of a network resource pool is the upper limit of bandwidth that the network resource pool can use.
Assigning a QoS priority tag to a network resource pool applies an 802.1p tag to all outgoing packets associated with that network resource pool.