Senior Network Security Engineer_ACI

The Senior Network Engineer is responsible for the design, operation, and support of enterprise network and data center environments, with a strong focus on Cisco ACI, Software-Defined Access (SDA), and network security operations. The role provides Level 3 support, ensures service availability, leads incident and change activities, and acts as a Subject Matter Expert (SME) for network and security technologies.

Responsibilities

ACI Operations & Device Management
•    Manage and operate Cisco ACI fabric, including APIC controllers, Spine, and Leaf switches.
•    Provide Level 3 (L3) support for Cisco ACI and Cisco SDA in an enterprise data center environment.
•    Perform day-to-day monitoring of fabric health, faults, events, and performance.
•    Ensure high availability, stability, and optimal performance of the ACI fabric.
•    Troubleshoot fabric faults, health score degradation, endpoint learning, and policy issues.

Configuration & Change Management
•    Configure and manage tenants, VRFs, Bridge Domains (BDs), EPGs, contracts, filters, and application profiles.
•    Implement L2/L3 connectivity, L3Out, vPC, and port-channel integrations.
•    Execute approved change requests in line with change management and ITIL processes.
•    Support ACI upgrades, patching, maintenance windows, and lifecycle management.
•    Perform fine-tuning and optimization of network devices across data centers, campus, and branch networks.

Incident, Problem & Service Management
•    Drive and manage security incidents, changes, and problems assigned to the Network Security Operations Team.
•    Perform root cause analysis (RCA) and implement corrective and preventive actions.
•    Ensure escalated incidents and service requests are resolved within defined SLAs/OLAs.
•    Resolve ticket-based requests in compliance with priority and SLA commitments.
•    Provide after-hours and on-call support for incidents, changes, and maintenance activities.

Enterprise Network & Security Operations
•    Configure, maintain, and support core switches, routers, firewalls, and access switches.
•    Handle day-to-day Network & Security operations, beyond ACI when required.
•    Support Systems, Virtualization, and Application teams for network-related issues.
•    Provide advanced troubleshooting support to branch IT technicians.
•    Work closely with NOC/SOC, server, virtualization, and application teams during incidents.

Governance, DR & Documentation
•    Act as a Subject Matter Expert (SME) for network and security technologies and project implementations.
•    Develop, maintain, and improve network SOPs, operational runbooks, and incident playbooks.
•    Plan, implement, and test Disaster Recovery (DR) and Business Continuity Plans (BCP), leading recovery efforts when required.
•    Create and maintain network inventory, topology diagrams, and technical documentation.

Vendor & Stakeholder Coordination
•    Coordinate with vendors and technology partners, including raising TAC cases and driving issues to closure.
•    Support device upgrades, replacements, migrations, data center moves, and new technology implementations.
•    Travel to client sites and data centers for installations, troubleshooting, audits, and migration activities.
•    Coordinate and support site visits across multiple locations as per SLA and project requirements

Standards & Compliance
•    Follow ITIL best practices for incident, change, and problem management.
•    Apply information security best practices across ACI, routing, switching, and network security operations.
•    Ensure network controls, policies, and procedures operate effectively and are continuously improved.

Qualifications

•    Bachelor’s degree in relevant discipline.
10+ years of relevant full-time experience in enterprise network environments.
•    Relevant certifications: CCNP / CCIE (preferred).
•    ITIL certification or strong ITIL process knowledge.
•    Experience working in Network Operations Centers (NOC) supporting large enterprise or multi-national clients.
•    Excellent written and verbal communication skills with the ability to articulate technology strategy and     operational risk.

Application Centric Infrastructure (ACI)
•    Hands-on experience in support, administration, installation, and upgrades of ACI environments.
•    Experience designing and building SDN-based data center networks using Cisco ACI, VMware NSX, and
•    OpenFlow-based solutions.
•    Secure onboarding of workloads using EPGs, contracts, filters, and L2Out/L3Out.
•    Integration of Cisco ACI with VMware NSX, including HCI/VxRail/VVD (Dell/EMC).
•    Configuration, testing, and validation of DR capabilities in multi-pod ACI architectures.
•    End-to-end knowledge of ACI firmware upgrades.
•    Troubleshooting ACI infrastructure and interoperability with traditional networks.
•    Knowledge of ACI Multi-Pod, Multi-Site, and Policy-Based Routing (PBR) is an advantage.

Software Defined Access (SDA) & ISE
•    Design, operation, and support of Cisco SDA campus networks.
•    Operate and maintain SDA fabric, including Edge, Border, Control Plane, DNAC, and ISE integration.
•    Implement and tune NAC policies using Cisco ISE, including IoT onboarding.
•    Monitor wired and wireless performance using SDA telemetry.
•    Troubleshoot SDA wired and wireless connectivity and performance issues.
•    Enforce security using TrustSec SGTs through ISE integration.
•    Plan and support IPv6 adoption as part of enterprise IP strategy.
Routing & Switching
•    Design and support large LAN and WAN environments, including VXLAN architectures.
•    Expertise in routing protocols: OSPF, EIGRP, BGP.
•    Extensive hands-on experience with Nexus, Catalyst, ISR/ASR routers, and Wireless LAN.
•    Strong understanding of VXLAN, Anycast Gateway, and data center routing designs.