System Center 2012 R2 Orchestrator, while second in the list, it is the first component to be upgraded. If you are going to add the new component Service Management Automation to your environment, you must install that now before upgrading Orchestrator.
Orchestrator Upgrade Sequence
Put all Orchestrator servers into an Operations Manager maintenance mode
Upgrade Orchestrator using the procedures outlined in the Upgrade Guide for Orchestrator.
Take the Orchestrator servers out of maintenance mode.
Do not upgrade the Orchestrator management packs on Operations Manager until after Operations Manager has been upgraded. Existing System Center 2012 SP1 Orchestrator management packs should continue to work.
Make sure that the following connections with Operations Manager continue to function:
Operations Manager agent
Operations Manager console (for IP communication)
Make sure that the following connections with Service Manager continue to function:
Make sure that the following connections with Configuration Manager continue to function:
Configuration Manager agent
Make sure that the IP connection with VMM continues to function.
Make sure that the IP connection with DPM continues to function.