Senior Network Engineer

Cognizant is seeking a Senior Network Engineer to design, implement, secure, operate, and optimize enterprise datacenter, campus, branch, wireless, and hybrid-cloud networks. This role requires advanced hands-on expertise in F5 BIG-IP, Palo Alto Networks, Cisco ACI, Cisco Nexus, Cisco Meraki, cloud networking, and enterprise DDI platforms. The engineer will serve as an L3 escalation point, lead major-incident troubleshooting, execute migrations and lifecycle upgrades, perform root cause analysis, and collaborate with security, cloud, application, server, and architecture teams.

Key Responsibilities

Network Engineering and L3 Operations

· Own complex P1/P2 incidents involving routing, switching, wireless, firewalls, load balancing, DNS, DHCP, IPAM, VPN, SD-WAN, and hybrid-cloud connectivity.

· Lead troubleshooting bridges, analyze packet captures and telemetry, restore service, document root cause, and implement permanent corrective actions.

· Prepare and execute implementation, validation, risk, dependency, and rollback plans for production changes and maintenance windows.

· Maintain network diagrams, standards, operating procedures, inventory, capacity plans, lifecycle roadmaps, and disaster-recovery documentation.

· Participate in on-call support, vulnerability remediation, compliance reviews, and vendor escalation activities.

F5 BIG-IP

· Configure and troubleshoot F5 BIG-IP LTM, including virtual servers, pools, nodes, monitors, profiles, SNAT, persistence, traffic policies, and SSL offload.

· Manage SSL/TLS certificates, ciphers, health checks, high availability, upgrades, backup, and recovery.

· Develop and troubleshoot iRules; experience with F5 DNS/GTM and Advanced WAF/ASM is preferred.

· Resolve latency, session persistence, SSL handshake, health-monitor, and traffic-distribution issues.

Palo Alto Networks

· Administer Palo Alto firewalls and Panorama, including zones, security policies, NAT, objects, App-ID, User-ID, URL filtering, threat profiles, and logging.

· Troubleshoot sessions, routing, policy matching, NAT, IPsec VPN, GlobalProtect, and application connectivity using logs, CLI tools, and packet captures.

· Perform PAN-OS upgrades, rulebase cleanup, recertification, migrations, and security-hardening activities.

Cisco ACI and Nexus

· Design and troubleshoot Cisco ACI fabrics using APIC, tenants, VRFs, bridge domains, application profiles, EPGs, contracts, filters, VMM integration, and L3Out.

· Configure Cisco Nexus 3K/5K/7K/9K platforms using VLANs, trunks, vPC, STP, HSRP, OSPF, BGP, VXLAN, and EVPN.

· Troubleshoot endpoint learning, contracts, routing adjacency, fabric health, interfaces, port channels, and Layer 2/Layer 3 connectivity.

· Support data-center migrations, segmentation, fabric expansion, software upgrades, and hardware refresh programs.

Cisco Meraki

· Design, deploy, and administer Cisco Meraki MX security appliances, MS switches, MR wireless access points, and the Meraki Dashboard.

· Configure Auto VPN, SD-WAN, traffic shaping, content and security policies, VLANs, DHCP, site-to-site VPN, client VPN, and high availability.

· Plan wireless networks using RF fundamentals, channel and power optimization, SSIDs, authentication, guest access, and roaming.

· Monitor organization and network health, analyze event logs and packet captures, manage templates and firmware, and troubleshoot branch, LAN, WAN, and Wi-Fi issues.

· Use Meraki APIs and automation workflows for inventory, configuration validation, monitoring, and large-scale deployment.

Cloud Networking

· Design and support Microsoft Azure and AWS connectivity across cloud and on-premises data centers.

· Azure: VNets, subnets, NSGs, UDRs, Load Balancer, Application Gateway, Azure Firewall, VPN Gateway, ExpressRoute, Private Link, and DNS.

· AWS: VPCs, subnets, route tables, Security Groups, NACLs, Transit Gateway, Elastic Load Balancing, Direct Connect, Route 53, PrivateLink, and Site-to-Site VPN.

· Troubleshoot asymmetric routing, overlapping address space, DNS, MTU, VPN, firewall, load-balancing, and cloud-to-data-center connectivity.

· Implement automation and Infrastructure as Code using Python, Ansible, Terraform, REST APIs, JSON, YAML, and Git.

DDI: DNS, DHCP and IPAM

· Administer enterprise DDI platforms, preferably Infoblox Grid, including DNS zones and records, DHCP scopes, reservations, failover, IPAM, and role-based access.

· Troubleshoot recursive and authoritative DNS, forwarding, delegation, DNSSEC, DHCP allocation, lease, and address-management issues.

· Maintain address plans, naming standards, DNS/DHCP resiliency, automation workflows, reports, upgrades, backups, and disaster-recovery procedures.

Required Qualifications

· Bachelor’s degree in computer science, Information Technology, Engineering, or equivalent practical experience.

· 8+ years of enterprise network engineering experience, including at least 3 years in a senior or L3 role.

· Advanced knowledge of TCP/IP, IPv4/IPv6, VLANs, STP, vPC, HSRP/VRRP, OSPF, BGP, VPN, QoS, NAT, wireless networking, and packet analysis.

· Hands-on production experience with F5 BIG-IP LTM, Palo Alto firewalls/Panorama, Cisco ACI/APIC, Cisco Nexus, and Cisco Meraki.

· Practical Azure and/or AWS networking experience, including private connectivity to on-premises environments.

· Hands-on DNS, DHCP, and IPAM experience with Infoblox or a comparable enterprise DDI solution.

· Experience with Wireshark, tcpdump, network monitoring, ITIL incident/problem/change processes, and technical documentation.

· Strong communication skills and the ability to coordinate high-severity incidents and complex changes.

This is a remote role. The salary range for this role is between $99,000 and $116,000 depending on the skills and qualifications of the candidate . Applications will be accepted till 11/11/2026.

Cognizant is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to sex, gender identity, sexual orientation, race, color, religion, national origin, disability, protected Veteran status, age, or any other characteristic protected by law.