IT Systems & Network Administrator

Parkside; City Of London; On-site; GBP 50,000 - 80,000; Full time

Job summary

Parkside in Heathrow is seeking an experienced IT Systems & Network Administrator to ensure day-to-day operation, maintenance, security and troubleshooting of the organisation’s IT infrastructure.

You will manage network security and firewall policies (SonicWall), administer VMware ESXi/vSphere hosts, support Windows Server/Active Directory, backups and disaster recovery, and provide user support in a busy depot environment.

Qualifications

• At least 5 years' experience in IT systems or network administration.
• Hands-on experience with SonicWall firewalls, VPNs and security hardening.
• Strong knowledge of VMware ESXi/vSphere.
• Experience with Windows Server and Active Directory.
• Excellent troubleshooting and customer-focused communication.

Responsibilities

• Configure, manage and monitor SonicWall firewalls and VPNs.
• Administer VMware ESXi/vSphere hosts and guests.
• Provide 1st and 2nd line IT support for hardware, software and network issues.
• Coordinate backups, disaster recovery and business continuity.
• Work with external vendors and manage IT procurement.

Skills

SonicWall firewalls

VMware ESXi/vSphere

Windows Server

Active Directory

Troubleshooting

Customer service

Tools

SonicWall

VMware ESXi/vSphere

Job description

IT Systems & Network Administrator

Location: Heathrow

Salary: £50,000 £80,000 depending on experience

Working arrangement: Office/depot based not a remote role

Our client is looking for an experienced and hands‑on IT Systems & Network Administrator to join their IT team. This is a key role responsible for the day-to-day operation, maintenance, security and troubleshooting of the organisation s IT infrastructure.

The successful candidate will have strong practical experience across network administration, firewall management and virtualisation, with particular expertise in SonicWall firewalls and VMware ESXi/vSphere.

Proven, demonstrable experience in a similar IT systems/network administration role is essential.

The Role You will be responsible for:

Network Security & Firewall Management

• Configure, manage and maintain SonicWall firewalls, including security policies, access rules, NAT, VPN and content filtering.
• Monitor firewall logs and network traffic to identify and respond to potential security threats.
• Carry out firmware upgrades, configuration backups and security hardening.
• Troubleshoot network connectivity and security issues.

Virtualisation & Server Administration

• Administer and maintain VMware ESXi/vSphere hosts and virtual machines.
• Provision virtual machines and manage resource allocation and performance.
• Manage snapshots, backups, migrations and capacity planning.
• Monitor the health, availability and performance of the virtual infrastructure.
• Support patching and ongoing infrastructure improvements.

End-User Support

• Provide 1st and 2nd line technical support to users across hardware, software, network and connectivity issues.
• Investigate and resolve support tickets efficiently and professionally.
• Provide a high level of customer service to internal users.
• Document incidents, solutions and standard operating procedures.

General IT Operations

• Support Windows Server, Active Directory and associated services.
• Assist with backup, disaster recovery and business continuity processes.
• Work with external IT vendors and service providers to resolve technical issues.
• Support IT procurement and infrastructure projects where required.

About You

We are looking for someone with:

• At least 5 years' experience in an IT Systems, Network Administration or similar infrastructure-focused role.
• Proven, hands‑on experience managing SonicWall firewalls, including configuration, VPNs, policies and troubleshooting.
• Strong working knowledge of VMware ESXi / vSphere.
• Excellent troubleshooting skills across desktop, server and network environments.
• Experience with Windows Server and Active Directory.
• A proactive approach to identifying and resolving technical issues.
• Strong problem‑solving skills and the ability to take ownership of issues through to resolution.
• Excellent communication skills and a customer-focused approach.
• The ability to work independently, prioritise workload and operate effectively in a busy environment.

Desirable Experience

The following would be advantageous:

• Relevant IT certifications such as SonicWall CSSA, VMware VCP, CompTIA Network+/Security+ or Microsoft certifications.
• Experience supporting multi-site or international environments.
• Knowledge of PowerShell or other scripting.
• Experience with IT infrastructure monitoring tools.
• Previous experience working within a busy operational or depot-based environment.

Salary & Working Arrangements

The salary will be dependent on experience:

• Intermediate-level candidate: up to £50,000
• Highly experienced candidate: up to £80,000

This is a fully office/depot-based position at Heathrow, and the role does not offer remote working.