Strong understanding of:z/OS I/O architecture (CHPIDs, control units, paths)FICON protocols and multi‑pathing conceptsI/O performance diagnostics (RMF, SMF, DCOLLECT)Experience working closely with z/OS systems programmersDesired Qualifications:Bachelor's degree in Computer Science, Information Systems, Engineering, or equivalent practical experienceAdvanced technical certifications and vendor training preferred. Required Qualifications:This position will require on call rotation support, some weekend and holiday support as well7 + years of hands‑on experience supporting enterprise mainframe storage environmentsProven experience in 24x7, mission‑critical, highly regulated production environmentsExperience operating at scale (multi‑data center, multi‑region, global firms).