Antonis Mortos
@antonismortos
I modernize mission-critical Linux, Kubernetes, and high-availability infrastructure for resilient enterprise services.
GreeceWhat I'm looking for
I am a Senior Linux and Infrastructure Administrator with extensive experience in enterprise IT environments, systems administration, virtualization, networking, cybersecurity and automation. My background includes Linux and Windows Server administration, Active Directory, Kubernetes, OpenShift, Proxmox, VMware, Hyper-V, Azure, Microsoft 365, HAProxy, VPN technologies, SQL environments and Bash/Python automation.
I have worked on large-scale infrastructure projects, including the migration of more than 100 systems and services to Linux and Kubernetes environments, high-availability platforms, SCADA infrastructure, network and security projects, and enterprise server environments. I have hands-on experience troubleshooting complex production issues, designing resilient infrastructure, managing virtualization clusters, implementing secure remote access solutions and automating repetitive administration tasks.
Cybersecurity is also an important part of my professional background. I hold certifications including CISSP, CISM, CISA, Security+, CEH Practical, GIAC GSEC, SSCP and CASP, which complement my practical infrastructure and systems experience.
I am particularly interested in Senior Linux Administrator, Kubernetes Administrator, Infrastructure Engineer, Systems Engineer, Platform Engineer and DevOps-oriented roles. I enjoy working with Linux, Kubernetes, automation, high availability, networking, security and modern infrastructure technologies. I am currently looking primarily for fully remote opportunities where I can contribute both technically and operationally to complex IT environments.
Experience
Work history, roles, and key accomplishments
Senior Information Technology System Administrator
Oct 2025 - Feb 2026 (4 months)
Held a key technical role in the migration of Greece's 112 Emergency Communications Service from legacy Microsoft Windows Server 2008 infrastructure to a modern Kubernetes-based Linux services architecture. Responsible for the migration, deployment, administration, and operational support of Linux-based services running within Kubernetes environments. Participated in the modernization of legacy Wi
13CS Systems Integrators | October 2025 - February 2026
Held a key technical role in the migration of Greece's 112 Emergency Communications Service from legacy Microsoft Windows Server 2008 infrastructure to a modern Kubernetes-based Linux services architecture.
Responsible for the migration, deployment, administration, and operational support of Linux-based services running within Kubernetes e
Information Technology System Administrator
Jun 2024 - Oct 2024 (4 months)
Managed, monitored, and maintained the company's IT infrastructure, including servers, network devices, and workstations. Administered and supported enterprise server environments. Provided technical support to end users, ensuring uninterrupted operation of hardware and software systems. Implemented security policies and performed system updates, backups, and access-control management. Configured
Managed, monitored, and maintained the company's IT infrastructure, including servers, network devices, and workstations.
Administered and supported enterprise server environments.
Provided technical support to end users, ensuring uninterrupted operation of hardware and software systems.
Implemented security policies and performed system updates, backups, and access-control management.
Con
Linux Senior Systems Administrator
Dec 2022 - Feb 2024 (1 year 2 months)
Participated in SCADA automation and infrastructure projects for EYDAP - Athens Water Supply and Sewerage Company, through GlobalGR.
Designed, administered, and supported high-availability virtualized infrastructure based on Proxmox VE HA clusters for business-critical industrial and monitoring environments.
Deployed and operated Kubernetes clusters on Proxmox VE High Availability infrastructu
Installed and maintained copper-based telecommunications infrastructure for residential customers.
Deployed vertical cabling systems.
Installed and supported telecommunications services for Cosmote and Wind customers.
Performed field troubleshooting, diagnostics, and installation support activities.
Employment was primarily through fixed-term monthly or quarterly contracts with organizations including ICAP, Adecco, Randstad, Telecroft, and Teleperformance. Managed and resolved technical incidents and service requests for major enterprise customers. Diagnosed and troubleshot LAN, WAN, networking, and telecommunications infrastructure issues. Used advanced monitoring and troubleshooting tools t
Managed and resolved technical incidents and service requests for major enterprise customers.
Diagnosed and troubleshot LAN, WAN, networking, and telecommunications infrastructure issues.
Used advanced monitoring and troubleshooting tools to identify and resolve complex technical problems.
Coordinated with internal technical teams and external partners for incident resolution.
Worked within st
Worked as a Field Engineer on enterprise telecommunications and IP communications projects.
Participated in international technical deployments, including projects in Iraq.
Supported complex distributed communications infrastructure.
Worked with SIP-based communications technologies.
Deployed and supported Asterisk PBX systems.
Provided installation, configuration, troubleshooting, and o
Provided consulting, installation, administration, and technical support services for Asterisk PBX solutions.
Installed and configured Windows Server-based network infrastructures.
Designed and implemented Samba Domain Controller environments on Debian Linux platforms.
Administered Linux-based server and network infrastructure.
Delivered networking and systems-integration services for smal
Monitored and administered server and network infrastructures, including Cisco and Juniper environments.
Configured Cisco networking equipment for Dial-Up and ADSL-based applications.
Supported industrial controllers and remote communication systems.
Participated in the deployment of a Network Operations Center (NOC) consisting of four 42U racks hosting servers and network equipment.
Parti
Education
Degrees, certifications, and relevant coursework
Brunel University of London
Computer Science & Information Technology
IT User Support: Provided technical support to students, academic staff, and visitors, ensuring the smooth operation of IT systems and services.
Infrastructure Management: Installation, maintenance, monitoring, and administration of hardware and software infrastructure.
Information Security: Applied information-security principles and best practices to support data protection and regulatory comp
Brunel University of London
Computer Science
IT User Support: Provided technical support to students, academic staff, and visitors, ensuring the smooth operation of IT systems and services. Infrastructure Management: Installation, maintenance, monitoring, and administration of hardware and software infrastructure. Information Security: Applied information-security principles and best practices to support data protection and regulatory compli
GIAC Certifications
GIAC Certified Incident Handler (GCIH)
CompTIA
CompTIA Advanced Security Practitioner (CASP)
ISC2
Systems Security Certified Practitioner (SSCP)
GIAC Certifications
GIAC Security Essentials (GSEC)
ISACA
Certified Information Security Manager (CISM)
EC-Council
Certified Ethical Hacker (CEH Practical)
CompTIA
CompTIA Security+ (SY0-701)
ISACA
Certified Information Systems Auditor (CISA)
ISC2
Certified Information Systems Security Professional (CISSP)
Microsoft
Microsoft Certified: Azure AI Engineer Associate
Microsoft
Microsoft Certified: Azure Fundamentals
Microsoft
Microsoft 365 Certified: Fundamentals
Cisco Networking Academy
Cisco Certified Design Associate (CCDA)
Cisco Networking Academy
Cisco CCVP
Cisco Networking Academy
Cisco Certified Internetwork Expert Security (CCIE-S)
Cisco Networking Academy
Cisco Certified Network Professional (CCNP)
Cisco Networking Academy
Cisco Certified Network Associate Routing and Switching (CCNA)
Tech stack
Software and tools used professionally
Availability
Location
GreeceAuthorized to work in
Salary expectations
Social media
Job categories
Skills
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