Service Profiles and Service Profile Templates
In the Cisco UCS, the server consists of two components:
- Compute node: This is the physical server, which provides the needed computing resources, such as CPUs, memory, local storage, and mezzanine adapters for physical connectivity.
- Service profile: This is the logical construct created in the Cisco UCSM that defines the following items related to the server:
- Identity: The combination of UUID, MAC addresses, and WWNN and WWPN addresses.
- Connectivity: This defines the number of vNICs and vHBAs that will be connected to the available communication paths and used by the server in an active manner.
- Policies: These are the pieces of the service profile that define the specific configuration and behavior related to the server and its components.
When a service profile, shown in Figure 17-21, is associated with a compute node, the result is a server that can be used. Without a service profile, the physical server cannot be used in the Cisco UCS. Also, there is a 1:1 relationship between the service profile and the compute node. At any given time, a service profile can be associated only with a single server, and a compute node can be associated only with a single service profile. This also means that for each physical server used in the Cisco UCS, a service profile is needed.
Figure 17-21 Cisco UCS Service Profile
During the association process, the Cisco UCSM pushes the service profile down to the CIMC of the server, together with the instruction to apply the configuration to the compute node. Then the CIMC reboots the server, as it needs the server to boot from a specialized operating system that resides in the storage of the CIMC that’s designed to take all the configuration from the service profile and apply it to the correct components of the server. Once this process has finished, the compute node is rebooted again. After the second reboot, the association of the service profile with the server has finished, all the needed configuration and identity values are applied to the server, and the server is ready for the installation of the operating system (a bare-metal OS or a virtualization hypervisor).
When the service profile is disassociated from the compute node, the same process is followed, but this time the configuration is reset to the default values, and the identity values are removed. The identity values always stay with the service profile, and when the service profile is associated with another server, the identity is applied to the new compute node.
The one challenge with the service profiles is that a service profile is needed for every server. To optimize the process of creating the needed amount of service profiles, especially when they are to be similar, you can use a service profile template.
The service profile template is a special type of service profile that is used to generate multiple service profiles at once. They will be similar, which means they will have the same configuration and policies, but each will have a unique identity. For example, all the generated service profiles will have the same BIOS configuration policy, the same vNICs and vHBAs, but each vNIC and vHBA will have a unique physical address. Because of this, during the process of creating multiple service profiles from a service profile template, you will need to get multiple unique identity values. This is achieved by using identity resource pools.
There are two types of service profile templates (detailed next), and it’s important to know the difference between them, as this affects the service profiles generated from them (see Figure 17-22):
Figure 17-22 Cisco UCS Service Profile Template Wizard
- Initial template: Service profiles are created from an initial template; they inherit all the properties of the template. Any changes to the initial template do not automatically propagate to the bound service profiles.
- Updating template: The service profiles created from an updating template inherit all the properties of the template and remain connected to the template. Any changes to the template automatically update the service profiles created from the template.
To create a service profile template, you must start the wizard, which is located in the Servers tab. It is similar to the Service Profile Wizard, as the major difference is that you have to set the type at the start.