Best Practices for Integrity Virtual Machines

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Virtual Networking
Reliability and Performance
The HP Auto Port Aggregation (APA) product may be used on the VM Host to provide high
availability for virtual networking. This is accomplished by defining your virtual switch(es) in terms of
the port created by APA (for example, lan900) rather than the LAN numbers associated with the
physical network interface cards (NICs). In doing so, all of the virtual NICs defined in terms of that
virtual switch automatically benefit from the high availability and aggregate throughput provided by
APA.
Adding Network Capacity
Network capacity can be increased in two basic ways – through the use of APA or definition of
additional, unused, virtual NICs in a VM configuration.
A physical NIC may be added to a VM Host and an APA configuration without rebooting the VM
Host. Due to the flexibility of APA, this card’s connection is immediately available to the APA port
and, hence, to the virtual switch using that APA port. The end result is an online increase in network
bandwidth for all VMs using that virtual switch.
Alternatively, one may define multiple virtual NICs in a VM configuration without using them all. In
particular, some ‘spare’ virtual NICs may be defined in terms of a virtual switch that does not exist.
This will not prevent the VM from being started, nor will it prevent the installation of the operating
system on that VM. These ‘spare’ virtual NICs will operate in a manner similar to any physical NIC
without a network connection. When there is a need for additional network bandwidth, a physical
NIC may be added to the VM Host (without rebooting) and then the virtual switch associated with
these ‘spares’ can be created such that it is associated with this new physical NIC. Once the virtual
switch is powered on, all of the virtual NICs will behave as if they had had just been connected to the
network (which, in fact, they have). Subsequently these virtual NICs may be configured and used by
the VMs in the desired manner.