Summary
Overview
Work History
Education
Skills
Accomplishments
Certification
Timeline
Generic

Joseph M. Liddell

Las Vegas,NV

Summary

Experienced with Linux system administration, network configuration, and infrastructure management. Utilizes scripting and automation to streamline processes and enhance operational efficiency. Strong understanding of security protocols and system optimization to ensure reliable and secure environments.

Overview

25
25
years of professional experience
1
1
Certification

Work History

Linux Engineer / Security Engineer

Criterion Systems / Cherokee Federal
Las Vegas, NV
03.2022 - Current
  • Authors / contributes to new and existing policy to ensure local policy and STIG compliance.
  • Reviews over 30 new and existing product change management requests per month for STIG compliance.
  • Reviews Tenable / various Appscan product results for STIG and local procedure compliance.
  • Configures, maintains, troubleshoots RedHat application servers and databases.
  • Authors, updates, and tests Ansible playbooks using version control via Git.
  • Uses RedHat Satellite to manage rpm repositories and update/manage licenses/inventory for over one thousand computers.
  • Kickstarts and configures physical and virtual RedHat Enterprise Linux servers.
  • Uses Ansible Controller to maintain server configurations and run automated processes.
  • Sets up RedHat servers as DNS caching servers for internal network name resolution.
  • Initializes RedHat systems as DHCP servers to handle DHCP needs on local networks.
  • Manages NFS and NTFS file shares between Linux and windows servers.
  • Installs, backs up, troubleshoots, and restores VMs in multiple hypervisor environments.
  • Migrates servers from old operating systems to new operating systems before end of Life.
  • Changed server over from IPtables to Firewalld to comply with security guidelines.
  • Helps ISSOs ensure servers comply with STIGs before and after release to production
  • Installs and configured Jira server for tracking organization projects and productivity.
  • Racks/Stacks new servers and equipment and decommissions/sanitizes old equipment.
  • Monitors Linux servers with Nagios, provides on call support for Linux services.
  • Helps integrate Linux and Windows DNS services and ensures entries are up to date.
  • Hardens servers to ensure they are in compliance with DISA hardening guidelines.

Information Systems Security Officer

Advanced Technological Solutions
Las Vegas, NV
10.2021 - 03.2022
  • Ensured equipment was hardened/configured IAW STIGs before joining to existing domains.
  • Documented network servers, clients, and networking equipment regulatory compliance.
  • Researched/implemented Security Technical Implementation Guide STIG controls.
  • Updated plan of action and milestones for risk mitigation/to ensure DISA STIG compliance.
  • Acted as organization’s security advisor and liaised with higher-level security managers.
  • Tacked and documented server, client, and networking equipment location with Visio.
  • Conducted ad-hoc client, server, and network support as needed.

Systems and Network Administrator

Invictus Technical Solutions
Las Vegas, NV
07.2021 - 10.2021
  • Managed user/groups on local Windows machines and via Active Directory.
  • Installed Windows server on computers and joined them to the domain.
  • Real-time Monitored network status and troubleshot/fixed network issues.
  • Tracked issues with ticketing service, resolved customer hardware/software issues.
  • Managed, Hyper-v, virtual servers/workstations.
  • Troubleshot issues with services provided by Docker containers.
  • Ran fiber and copper networking lines and racked and stacked servers.

System Engineer

Spiral Solutions and Technology
Omaha, NE
01.2020 - 07.2021
  • Managed user/groups/services on local Windows for hundreds of users and machines and via Active Directory.
  • Installed, managed, and monitored, endpoint Anti-Virus protection.
  • Configured network interfaces with dynamic and static IPs on Microsoft systems.
  • Integrating Linux and Windows servers and services on a Windows Active Directory Domain.
  • Managed and troubleshot issues with API services on Windows servers.
  • Created, Hyper-v, VMware, Virtual box, and KVM virtual servers/workstations.
  • Managed Linux users and groups, and discretionary and mandatory access control.
  • Researched and implemented Open-source software solutions to fit corporate needs.
  • Installed and configured Docker and Kubernetes clusters.
  • Installed, configured and monitored Antivirus and endpoint security software.
  • Hardened Linux/Windows systems according to Government/organization standards.
  • Configured Linux/Windows Firewalls and Access lists.
  • Drew up office diagrams to facilitate equipment setup and network documentation.
  • Solved Linux and Windows server and workstation problems trouble tickets for customers.

Language Analyst

USAF Cryptologic
Various Locations
06.2000 - 01.2020
  • Security Manager I oversaw personnel and physical security for our building/organization for two different locations and hundreds of personnel.
  • Helped manage security and cleanup / sanitization efforts after a natural disaster.
  • Worked in a computer programming office providing hardware and network cable support.
  • Recorded office equipment inventory and conducted equipment accountability auditing.
  • Learned to install and maintain several different .rpm and .deb-based Linux distributions.
  • Used Unix and Unix emulators for operations both as a user and an instructor.

Education

Bachelor of Liberal Arts - Korean

Excelsior College
Albany, New York
06-2002

Skills

  • Linux system administration
  • Git version control
  • Docker containers
  • Virtualization technologies
  • GitHub management
  • Ansible automation
  • Continuous integration
  • Network configuration
  • Patch management
  • Architecture review

Accomplishments

  • Collaborated with team of eight to upgrade thousands of computers from RedHat Enterprise Linux 7 to RedHat Enterprise Linux 8.
  • Wrote standard operating procedure for remote kick-starting and configuring Jira and Bitbucket.
  • Helped team ensure that patches for thousands of computers were tested in a development network and patched in production.
  • In charge of implementing and maintaining enterprise web application via Docker for an Enterprise Network.
  • Set up and maintained hundreds of computers in development and test environments.

Certification

CompTIA A+

CompTIA Network+

CompTIA Security+

CompTIA Linux+

CompTIA Cloud+
Cisco Certified Network Associate

RedHat Certified System Administrator

Timeline

Linux Engineer / Security Engineer

Criterion Systems / Cherokee Federal
03.2022 - Current

Information Systems Security Officer

Advanced Technological Solutions
10.2021 - 03.2022

Systems and Network Administrator

Invictus Technical Solutions
07.2021 - 10.2021

System Engineer

Spiral Solutions and Technology
01.2020 - 07.2021

Language Analyst

USAF Cryptologic
06.2000 - 01.2020

Bachelor of Liberal Arts - Korean

Excelsior College
Joseph M. Liddell