Senior Network Engineer - Arista & Automation Specialist

Square One Resources; City Of London; Remote; GBP 80,000 - 100,000; Full time

Job summary

A leading company seeks a Senior Network Engineer with expertise in Arista-based networks and network automation. The role involves designing and optimizing low-latency infrastructure, supporting global data centers, and driving operational excellence through automation. Candidates should have strong experience with Arista EOS, routing protocols, and network automation tools.

Qualifications

• Strong hands-on experience with Arista EOS.
• Deep knowledge of routing protocols (BGP, OSPF, EVPN).
• Experience with network automation using Python and Ansible.

Responsibilities

• Lead the design, deployment, and optimization of Arista-based data center networks.
• Build and maintain network automation scripts using Python.
• Provide senior-level L3 support and mentor junior engineers.

Skills

BGP

EVPN

Multicast

Python

Ansible

Nornir

Education

Relevant Certifications (CCNP R&S, CCNP DC, etc.)

Job description

Job Title: Senior Network Engineer - Arista & Automation Specialist (Low-Latency DC Focus)
Location: United Kingdom (Remote, with occasional site visits if needed)
Day Rate: £420 - £430 Per Day (Inside IR35)
Contract Type: Long-term rolling contract

Company Introduction

We are seeking an experienced Senior Network Engineer with a proven background in Arista-based data centre networks and a strong focus on network automation. The successful candidate will join a highly technical environment supporting the design, deployment, and ongoing optimisation of low-latency, high-availability infrastructure across global data centres.

You'll work with a modern network stack (Arista EOS, CloudVision, Python, Nornir, Ansible) and interface closely with architecture, security, and DevOps teams to drive automation and resiliency in a performance-critical environment.

Job Responsibilities/Objectives

• Lead the design, deployment, and optimisation of Arista-based data centre networks, with a focus on low-latency and high resilience.
• Configure and troubleshoot BGP, EVPN (VXLAN), and Multicast (PIM, IGMP) in complex enterprise environments.
• Use Arista CloudVision for orchestration, telemetry, and automated configuration management across global environments.
• Build and maintain network automation scripts using Python, Nornir, and Ansible, ensuring repeatability and alignment with infrastructure-as-code practices.
• Support large-scale hardware refreshes and migrations from Cisco to Arista, ensuring minimal downtime in production environments.
• Collaborate with global teams to align network delivery with broader CI/CD pipelines, and implement proactive monitoring and remediation frameworks.
• Provide senior-level L3 support, mentor junior engineers, and drive best practices in operational excellence.

Required Skills/Experience
The ideal candidate will have the following:

• Strong hands-on experience with Arista EOS in complex enterprise or global data centre environments.
• Deep knowledge of routing protocols (BGP, OSPF, EVPN) and Multicast technologies.
• Demonstrated experience working with Arista CloudVision in both greenfield and brownfield deployments.
• Background in low-latency networks - ideally within financial services or other performance-critical environments.
• Proficiency in network automation using Python, Ansible, Nornir, and version control tools (Git).
• Solid grounding in Layer 2/3 principles, troubleshooting, and production change management.
• Excellent documentation and communication skills; able to work collaboratively across global teams.

Desirable Skills/Experience
Although not essential, the following skills are desired by the client:

• Experience with Cisco Nexus platforms (2k-9k) and migrations to Arista.
• Exposure to network security platforms (Palo Alto, Fortinet, F5).
• Familiarity with CI/CD pipelines and infrastructure-as-code principles.
• Experience with monitoring tools (SolarWinds, PRTG, Logic Monitor) and SNOW for incident/change management.
• Relevant certifications (CCNP R&S, CCNP DC, PCNSA, ACI Specialist, or CCIE in progress) are a strong plus.

If you are interested in this opportunity, please apply now with your updated CV in Microsoft Word/PDF format.

Disclaimer
Notwithstanding any guidelines given to level of experience sought, we will consider candidates from outside this range if they can demonstrate the necessary competencies.

Square One is acting as both an employment agency and an employment business, and is an equal opportunities recruitment business. Square One embraces diversity and will treat everyone equally. Please see our website for our full diversity statement.