Apple likely had its servers custom-made to fit data center operations, McCarron said. For example, data centers may have thousands of servers based on one chip architecture running cloud applications, and a small set of servers on another architecture dedicated to other operations.

An Apple listing for an requires the applicant to know the operation of SAP software on AIX. SAP is known for its business management and ERP (enterprise resource planning) software, and that suggests that the AIX servers in the data center may be there for back-office tasks, McCarron said.

"Sounds like a data center running high-end hardware," McCarron said.

A representative of Apple could not immediately be reached to comment about the job posting.