Senior System and Network Administrator

Salary: £50,000 - 55,000 per year

Requirements:

• Senior-level experience in system administration, network administration, or infrastructure engineering
• Strong knowledge of network architecture and network design
• Strong understanding of TCP/IP, IPv4, subnetting, routing, switching, VLANs, NAT, DNS, DHCP, and VPN technologies
• Experience configuring and maintaining firewalls, routers, switches, and wireless networks
• Strong Ubuntu and Linux administration skills
• Strong Bash scripting skills
• Experience managing Linux services, systemd, package management, storage, networking, permissions, and logs
• Practical AWS administration experience
• Understanding of AWS networking, IAM, security groups, compute, storage, monitoring, and backup
• Experience administering public and private DNS
• Experience administering mail servers or enterprise email infrastructure
• Understanding of SMTP, IMAP, SPF, DKIM, DMARC, mail relays, spam filtering, and email-delivery troubleshooting

Responsibilities:

• Design, operate, and improve office, production, laboratory, and remote-access network infrastructure
• Define network architecture, address plans, routing, segmentation, and security boundaries
• Configure and maintain switches, routers, firewalls, wireless networks, VPN gateways, and related network equipment
• Implement VLANs, routing policies, firewall rules, NAT, site-to-site VPNs, and remote-access VPNs
• Maintain secure connectivity between offices, cloud environments, industrial systems, development infrastructure, and remote users
• Administer Ubuntu and other Linux-based servers
• Manage AWS infrastructure, including compute, storage, networking, IAM, security groups, backups, and monitoring
• Administer DNS zones, domain registrations, records, certificates, and related infrastructure
• Maintain our company email infrastructure and email-delivery configuration
• Manage mail routing, authentication, anti-spam controls, SPF, DKIM, DMARC, and troubleshoot delivery issues
• Operate monitoring and alerting infrastructure using Zabbix and related tools
• Define monitoring coverage for servers, networks, services, certificates, backups, storage, and cloud resources
• Develop Bash scripts and other automation for provisioning, maintenance, monitoring, and incident response
• Manage user accounts, permissions, SSH access, privileged access, service accounts, and access revocation
• Maintain backup and disaster-recovery systems
• Regularly test backup restoration and disaster-recovery procedures
• Perform server hardening, vulnerability remediation, patch management, and security reviews

Technologies:

• AWS
• Bash
• Cloud
• Firewall
• IAM
• Linux
• NAT
• Network
• Security
• TCP/IP
• Ubuntu
• VPN
• Zabbix

More:

We are a leading marine energy company based on Merseyside and operating globally for maritime clients. We provide battery and hybrid energy solutions used across the maritime industry, supported worldwide by remote and on-site monitoring to deliver first-class customer service. This is a full-time, permanent Senior System and Network Administrator position, and we provide full training. The role takes ownership of our IT infrastructure, networks, cloud environments, servers, monitoring systems, and core internal services, with a focus on improving their architecture, security, reliability, documentation, and operational efficiency. The starting salary is £50,000 per year, rising in guaranteed £2,500 annual increments to £52,500 after six months and £55,000 after one year. Benefits include 22 days of holiday plus eight bank holidays, a personal pension scheme, and an excellent benefits package.

last updated 41 week of 2026