A service profile is the principle feature of the UCS platform that enables stateless computing. Service profiles radically improve server provisioning and troubleshooting. Servers can be provisioned in software even before the delivery of physical hardware; in case of hardware failure, it can be replaced by associating the existing software service profile of the failed server without going through any painstaking firmware upgrade procedures.

UCS Manager abstracts a service profile from the configurations available under the following categories:

• Identity and resource pools: As explained in Chapter 7, Creating Identity Resource Pools, Policies, and Templates, identity and resource pools provide silos for computing node-unique characteristics such as MAC addresses, WWNs, and UUIDs. These identities uniquely recognize systems on the network. UCS servers abstract these physical identities from software pools available from UCS Manager instead of using burned hardware identities.
• Service policies: Service policies, which will be explained later in this chapter, provide different configurations for the UCS servers including BIOS settings, firmware versions, adapter policies, scrub policies, IPMI policies, and so on.
• Templates: Templates provide the pre-configured settings that can be reused for rapid deployment of servers such as vNIC, vHBA, and service profile templates. vNIC or vHBA templates provide the customized configuration of network adapter and host bus adapter that can be recalled to create multiple interfaces for any server where a service profile template can be used to create multiple service profiles with desired identities, resource pools, and policies. A service profile combines information and features abstracted from identity and resource pools, server policies, and vNIC/vHBA templates. It is a software entity residing in UCS Manager that provides a complete server role when associated with a stateless physical hardware server. Service profile information and association is depicted in the following diagram:

The preceding diagram shows how a service profile provides all features and identities to the physical server by extracting those identities, resources, and policies from different configurations in the form of templates, pools, and policies. It is possible to create a service profile directly from pools and policies; however, it is recommended to create service profile templates, which could be applied to any number of similar servers, reducing the management effort.