Subject Matter Expert (Support&Ops)

Job description

Job Description: Mainframe Network Engineer / SpecialistRole SummaryWe are looking for an experienced Mainframe Network Engineer / Specialist to support the administration, availability, performance, security, connectivity, and modernisation of enterprise IBM Z networking environments. The role requires strong hands-on expertise in z/OS Communications Server, TCP/IP, VTAM/SNA, network configuration, troubleshooting, resiliency, security, and performance management .The individual will work closely with Mainframe infrastructure, network, security, application, middleware, operations, and vendor teams to ensure highly available, secure, and resilient connectivity for business-critical Mainframe platforms. Key Responsibilities Key ResponsibilitiesInstall, configure, maintain, upgrade, and support z/OS Communications Server and associated Mainframe networking components.Administer and troubleshoot TCP/IP, VTAM, SNA, Enterprise Extender, OSA, HiperSockets, and related IBM Z networking technologies .Configure and maintain TCP/IP profiles, network interfaces, routes, ports, resolver configurations, VIPA/DVIPA, and network connectivity within z/OS environments.Manage VTAM configurations , including major nodes, application definitions, cross-domain resources, and network connectivity.Support high-availability and workload-distribution configurations using technologies such as DVIPA, Sysplex Distributor, VIPA Takeover, and dynamic routing .Monitor Mainframe network availability, utilisation, capacity, latency, connectivity, and performance and proactively address potential issues.Perform problem determination for network-related incidents using z/OS system commands, Communications Server diagnostics, packet traces, logs, SMF records, network traces, and monitoring tools .Support network connectivity for Mainframe subsystems and middleware including CICS, Db2, IMS, IBM MQ, FTP/SFTP, Connect:Direct, web services, APIs, and application interfaces , depending on the environment.Configure and support secure Mainframe communications using TLS/SSL, AT-TLS, digital certificates, RACF key rings, encryption, and secure network protocols .Support DNS, name resolution, routing, firewall, proxy, load-balancing, and connectivity requirements in collaboration with enterprise network and security teams.Support IBM Z hardware network connectivity including OSA-Express, HiperSockets, LPAR connectivity, and HMC-related network considerations .Participate in IPL, DR exercises, resiliency testing, network failover, business-continuity testing, and recovery activities .Support software maintenance, upgrades, PTF application, lifecycle activities, and compatibility assessments related to z/OS Communications Server and networking components .Develop and maintain REXX, JCL, scripts, or other automation to improve network monitoring, diagnostics, configuration, and operational efficiency.Maintain technical documentation including network diagrams, configuration records, SOPs, operational procedures, recovery procedures, and audit evidence .Collaborate with Mainframe system programmers, enterprise networking, security, application, middleware, storage, automation, and service-management teams for incident, problem, change, and service-improvement activities.Support network security reviews, vulnerability remediation, compliance requirements, certificate renewals, and security-hardening activities .Identify opportunities for automation, network modernisation, observability, security improvement, and operational optimisation across the Mainframe network environment. Skill Requirements Required Technical SkillsStrong hands-on knowledge of IBM z/OS Communications Server TCP/IP on z/OS VTAM / SNA networking Enterprise Extender (EE) TCP/IP profile configuration, routing, interfaces, ports, and network services VIPA / DVIPA, Sysplex Distributor, and high-availability networking concepts OSA-Express and HiperSockets DNS and z/OS resolver configuration TLS/SSL and Application Transparent TLS (AT-TLS) RACF key rings, digital certificates, and secure communications concepts Network diagnostics and troubleshooting using packet traces, logs, system commands, SMF records, and monitoring tools Knowledge of networking requirements for CICS, Db2, IMS, IBM MQ, FTP/SFTP, Connect:Direct, and other Mainframe services TSO/ISPF and JCL REXX / scripting and operational automation Knowledge of IP routing, firewalls, ports, load balancing, network segmentation, and security concepts Incident, problem, and change managementStrong troubleshooting and root-cause-analysis skillsPreferred SkillsExposure to one or more of the following would be advantageous: IBM Z hardware, LPAR and PR/SM concepts Parallel Sysplex and Sysplex networking CICS, Db2, IMS, IBM MQ HMC and OSA configuration concepts SNA, APPN, HPR and Enterprise Extender FTP, SFTP, FTPS, Connect:Direct and managed file-transfer technologies Network Management Interface (NMI), SMF and network-monitoring tools Mainframe network monitoring, performance, and observability solutions RACF, digital certificates, PKI, TLS, AT-TLS, ICSF, and encryption technologies Enterprise network technologies and platforms such as DNS, firewall, proxy, load balancer, VPN, and IPAM Disaster recovery, network resiliency, business continuity, and failover testing Ansible, Python, Git, REST APIs, or DevOps automation in a Mainframe environmentMainframe integration with distributed, hybrid-cloud, API, and modern application environments Mainframe network security, segmentation, Zero Trust , and security-hardening concepts Other Requirements ExperienceRelevant hands-on experience in Mainframe network engineering, z/OS Communications Server administration, infrastructure support, or network operations .Experience supporting business-critical enterprise Mainframe environments with high availability and resiliency requirements.Experience administering and troubleshooting TCP/IP, VTAM/SNA, OSA, DVIPA, Sysplex networking, and secure Mainframe connectivity .Experience supporting network upgrades, connectivity changes, incident resolution, performance analysis, DR, and resiliency activities .Experience working with network security, TLS/SSL, certificates, firewall connectivity, and secure communication requirements .Experience working within structured ITIL-based Incident, Problem, Change, and Release Management processes.Desired ProfileStrong analytical and problem-solving capability.Ability to independently troubleshoot complex Mainframe network, connectivity, and performance issues .Strong understanding of enterprise networking concepts and their implementation within IBM Z environments .Good written and verbal communication skills.Comfortable working with global Mainframe, network, security, application, middleware, infrastructure, and vendor teams .Strong focus on availability, resiliency, security, performance, documentation, automation, and continuous improvement .Ability to coordinate complex connectivity issues across Mainframe and distributed network environments . Apply now Information at a Glance Why HCLTech? At HCLTech, you'll supercharge your potential. You'll find your career. And you'll find your spark. All at a place that knows that helping its customers stay on top starts by putting its people first. HCLTech is a global technology company, home to more than 230,000 people across 60 countries, delivering industry-leading capabilities centered around digital, engineering, cloud and AI, powered by a broad portfolio of technology services and products. We work with clients across all major verticals, providing industry solutions for Financial Services, Manufacturing, Life Sciences and Healthcare, Technology and Services, Telecom and Media, Retail and CPG, and Public Services. Consolidated revenues as of 12 months ending September 2026 totaled $14.8 billion. Disclaimer Privacy Statement Terms of use Sitemap Raise a Grievance We use cookies on our site. Please read more about