L3 Network Engineer

L3 Network Engineer

Experience: 7–10 Years

Employment Type: Full-time

Location: Chennai

About the Role

We are looking for an experienced L3 Network Engineer to join our Network Operations team. The role involves handling complex network incidents, advanced troubleshooting, network changes, technical escalations, and infrastructure projects across enterprise customer environments.

The ideal candidate should have strong hands-on experience in Cisco networking, routing & switching, firewalls, VPN, SD-WAN, wireless, network security and advanced troubleshooting.

Key Responsibilities

· Provide L3 technical support for complex network incidents escalated from L1 and L2 teams.

· Troubleshoot and resolve complex LAN, WAN, WLAN, VPN and Internet connectivity issues.

· Perform advanced troubleshooting across enterprise network infrastructure.

· Configure, troubleshoot and optimize Cisco routers and switches.

· Troubleshoot routing protocols including BGP, OSPF, EIGRP and static routing.

· Troubleshoot switching technologies including VLANs, trunking, STP/RSTP/MST, EtherChannel and LACP.

· Troubleshoot HSRP, VRRP and network redundancy/high-availability configurations.

· Troubleshoot routing loops, asymmetric routing, packet loss, latency and network instability.

· Analyze network traffic and perform packet-level troubleshooting using Wireshark and packet captures.

· Troubleshoot MPLS, SD-WAN, Internet circuits and WAN connectivity.

· Configure and troubleshoot IPsec, SSL VPN, GRE and site-to-site VPNs.

· Troubleshoot enterprise firewalls including Fortinet, Palo Alto and Cisco ASA/Firepower.

· Troubleshoot firewall policies, NAT, security rules, VPN tunnels and connectivity issues.

· Support enterprise wireless infrastructure including Cisco, Aruba and Meraki environments.

· Troubleshoot wireless authentication, roaming, RF, coverage, performance and connectivity issues.

· Monitor network health and performance using PRTG, SolarWinds or equivalent monitoring platforms.

· Analyze network alerts, logs, SNMP data, syslog and performance metrics to identify root causes.

· Take ownership of Major Incidents and coordinate technical resolution within agreed SLAs.

· Participate in RCA and Problem Management activities for recurring and critical network issues.

· Prepare detailed Root Cause Analysis (RCA) and corrective/preventive action reports.

· Perform network configuration changes, upgrades and maintenance activities following the approved Change Management process.

· Participate in network migrations, infrastructure upgrades and technology refresh projects.

· Review existing network configurations and identify opportunities for performance, availability and security improvements.

· Validate network designs and provide technical recommendations for new implementations.

· Coordinate with ISPs, OEMs, vendors and third-party service providers for complex issue resolution.

· Work closely with internal infrastructure, security, service desk and application teams during troubleshooting.

· Participate in customer technical calls and provide regular updates on critical incidents and planned changes.

· Maintain accurate network diagrams, configuration documents, SOPs, troubleshooting guides and knowledge articles.

· Ensure network documentation and CMDB information are updated following infrastructure changes.

· Perform configuration reviews and identify potential network risks or single points of failure.

· Support network capacity planning and identify bandwidth, performance and infrastructure requirements.

· Participate in network audits, compliance activities and security reviews where required.

· Develop and improve network troubleshooting procedures, SOPs and operational runbooks.

· Mentor and provide technical guidance to L1/L2 Network Engineers.

· Conduct knowledge-sharing sessions and technical training for junior engineers.

· Identify recurring incidents and recommend permanent solutions to reduce incident volume.

· Ensure all incidents, changes and problem records are properly documented in the ITSM tool.

· Maintain compliance with SLA, ITIL, security and operational processes.

· Participate in 24×7 on-call / rotational support for critical network incidents.

Required Skills

· 6–10 years of experience in Enterprise Networking / Network Operations.

· Strong hands-on experience with Cisco routers and switches.

· Strong knowledge of BGP, OSPF, EIGRP, VLAN, STP, HSRP/VRRP and TCP/IP.

· Experience with firewalls, VPN and network security.

· Experience with SD-WAN, MPLS and WAN technologies.

· Strong knowledge of enterprise network troubleshooting methodologies.

· Hands-on experience with Wireshark and packet analysis.

· Experience with network monitoring tools such as PRTG, SolarWinds or equivalent.

· Good understanding of ITIL, Incident, Problem and Change Management.

· Strong analytical and problem-solving skills.

· Excellent communication and customer-handling skills.

· Ability to work independently and handle critical incidents under pressure.

· Willingness to work in a 24×7 / rotational support environment.

Preferred Certifications

· CCNP Enterprise

· CCNA

· Fortinet / Palo Alto certification

· Aruba / Meraki certification

· ITIL Foundation