IBM RackSwitch G8000, Application Manual

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RackSwitch G8000: Application Guide
VM Policy Bandwidth Control
In a virtualized environment where VEs can migrate between hypervisors and thus
move among different ports on the switch, traffic bandwidth policies must be
attached to VEs, rather than to a specific switch port.
VM Policy Bandwidth Control allows the administrator to specify the amount of data
the switch will permit to flow from a particular VE, without defining a complicated
matrix of ACLs or VMAPs for all port combinations where a VE may appear.
VM Policy Bandwidth Control Commands
VM Policy Bandwidth Control can be configured using the following configuration
commands:
Bandwidth allocation can be defined for transmit (TX) trafficonly. Because
bandwidth allocation is specified from the perspective of the VE, the switch
command for TX Rate Control (
txrate
) sets the data rate to be sent from the VM to
the switch.
The committed rate is specified in multiples of 64 kbps, from 64 to 10,000,000. The
maximum burst rate is specified as 32, 64, 128, 256, 1024, 2048, or 4096 kb. If both
the committed rate and burst are set to 0, bandwidth control will be disabled.
When
txrate
is specified, the switch automatically selects an available ACL for
internal use with bandwidth control. Optionally, if automatic ACL selection is not
desired, a specific ACL may be selected. If there are no unassigned ACLs available,
txrate
cannot be configured.
Bandwidth Policies vs. Bandwidth Shaping
VM Profile Bandwidth Shaping differs from VM Policy Bandwidth Control.
VM Profile Bandwidth Shaping (see “VM Profiles” on page 168 ) is configured per
VM group and is enforced on the server by a virtual switch in the hypervisor.
Shaping is unidirectional and limits traffic transmitted from the virtual switch to the
G8000. Shaping is performed prior to transmit VM Policy Bandwidth Control. If the
egress traffic for a virtual switch port group exceeds shaping parameters, the traffic
is dropped by the virtual switch in the hypervisor. Shaping uses server CPU
resources, but prevents extra traffic from consuming bandwidth between the server
and the G8000.
VM Policy Bandwidth Control is configured per VE, and can be set independently for
transmit traffic. Bandwidth policies are enforced by the G8000. VE traffic that
exceeds configured levels is dropped by the switch upon ingress. Setting
txrate
uses ACL resources on the switch.
Bandwidth shaping and bandwidth policies can be used separately or in concert.
RS G8000(config)#
virt vmpolicy vmbwidth
<VM MAC>
|
<index>
|
<UUID>
|
<IPv4 address>
|
<name>
?
txrate
<committed rate> <burst>
[
<ACL number>
]
(Set the VM to switch rate)
bwctrl
(Enable bandwidth control)