Attached is a document outlining High Availability (HA) options to a customer.  


Virtual Machine Requirements

1. Make sure that the VM is properly block aligned (do not assume it is just because your VMWare/Hypervisor vendor says it is).

2. Make sure that the VM runs with no %ready time

3. Make sure that the VM grabs its entire allocation of memory on startup (Memory Reservation) and holds onto it (it needs to be contiguous) (This is the one that impacts garbage collection most)

4. Reserving the defined Heap space or memory allocation of the database server is required


Q/A:

Can a customer run PNE using a VMWARE HA approach rather than the current PNE HA?

You can use VM images for doing high availability. Follow the guidelines for virtual machines above.  Most of the HA installations are using virtual machines.


How does that work with the licenses? Are the VMs both the same HW ID?

When you license the system, it is shared identity today.  In the upcoming 4.0 release, when you license the failover system, it will have a place to enter the system 1 and 2.


Does HA this way require or use VM clustering?

The OS can be configured either way (cluster or no cluster).  PulseNET uses HA at the application layer.

We suggest that the best way for HA is through OS clustering but it can be expensive compared to other methods.



GE Support Policy on Virtualization
Virtualization is a technique for hiding the physical characteristics of computing resources from the way in which other systems, applications or end users interact with those resources. It is able to make a single physical resource, such as a server, operating system, application or storage device appear to function as multiple logical devices. It can also make multiple physical resources such as storage devices or servers appear as a single logical resource. As a result virtualization enables IT departments to increase the utilization of resources, increase high availability, and simplify back-up, systems administration and recovery procedures. It also allows IT departments to be more responsive to the dynamic needs of the business. Examples of virtualization technologies include VMware ESX Server, Citrix/XenServer and Microsoft Windows Server 2008 Hyper-V.

GE Software products leverage the binary compatibility offered through virtualization technologies, which provide complete transparency to the operating systems and applications deployed. As a result, for all casework received where the GE product is being used in a virtual environment, GE Support will assume that the problem is common to both native and virtual operating environments, and that we will only require the customer to recreate the problem in a native environment if and when there is reason to believe that the problem is unique to the virtual environment itself.

From a purely functional perspective, GE products will operate in exactly the same way, however GE Software can make no guarantees with respect to performance or scalability in a virtualization environment running multiple virtual instances. Configuration aspects such as CPU, memory availability, I/O subsystem and network infrastructure can all influence such a deployment, which should be given careful consideration to ensure the virtual layer has the necessary resources available to provide a satisfactory user experience.