XenServer Administration Handbook

Chapter 5. Deployment Blueprint

In this chapter, we’ll cover some of the decision points you’ll want to go through in order to optimize the design of your XenServer deployment. While it might be tempting to call these “best practices,” it would be more accurate to describe them as a simple decision tree. The core topics covered are storage and networking as they relate to creating a stable deployment with predictable performance.

Start with Storage

All VMs will need their disks to be stored someplace, and it’s important in your blueprint to decide how the VM interacts with the resources you provide. In Chapter 4, we covered pools versus standalone hosts, shared versus local storage, defining an input/output (I/O) envelope, and designing for failure.

Each of these items has storage at its core, so in the following sections, we’ll provide a basic decision matrix.

Local Versus Shared Storage

If you use local storage in a resource pool, all I/O associated with those VMs is local to the host. This can be beneficial if the VMs have compatible I/O requirements. One of the drawbacks to local storage is that VM migration will be more resource intensive, slower, and have a greater user impact than with shared storage due to the usage of storage migration. During storage migration, the underlying disk is copied from the source storage to destination storage, and this copy occurs over a management network. Because the primary management network is used for all pool operations, ...