Senior Systems Administration

This position requires office presence of a minimum of 5 days per week and is only located in the location(s) posted. No relocation is offered. What you’ll do: Monitoring, Troubleshooting, and Service Availability: Ensure continual service availability through monitoring, troubleshooting, and analyzing problems to prevent service disruptions and to identify root causes along with mitigations to prevent future occurrences. Security management, compliance, and data integrity: Perform security compliance, auditing, and remediation, perform set up, maintenance, and monitoring of backups, along with routine hardware and software audits to ensure configuration and standards compliance. DevOps and Standards: Develop, promote, and curate standard operating/method of procedures in conjunction with risk assessments to reduce hazards to the network and new solutions being developed, while also maintaining and continuously improving tools, ad-hoc scripting, and automation infrastructure for configuration management, maintenance, testing, auditing, problem remediation and capacity planning. Vendor Management: Collaborate with and manage vendors to drive defect resolution and enhancements for internal customers to meet departmental or enterprise business needs, in addition to providing extended support as required. Software Installation, Upgrades, and Readiness Testing: Perform and schedule software installations and upgrades to operating systems and layered software packages and may also perform Operational Readiness Testing and Operational Acceptance Testing. What you’ll need: Ensure continual service availability by proactively monitoring, analyzing, and resolving issues in production on-premises cloud infrastructure which will require working with teams such as architecture, labs, other operations support teams, and cloud tenants to maintain maximum stability, performance, and security of the current and future cloud environments via the DevOps model while utilizing subject matter expertise in at least some of the following: Linux, cloud computing, Kubernetes, Open. What you’ll bring: The Senior System Administrator is responsible for the design, implementation, operation, and optimization of enterprise email transport systems. This role provides advanced technical support for Linux-based messaging environments, including Sendmail/Postfix MTAs and associated SMTP infrastructure, ensuring reliable, secure, and scalable email delivery across the organization. The position requires deep expertise in Linux system administration, email protocols, and enterprise messaging architecture, with a strong focus on operational excellence, security, and automation. Email Infrastructure & Operations Administer and support enterprise email transport systems, including Sendmail and/or Postfix mail transfer agents (MTAs) Monitor and manage inbound and outbound email traffic across corporate relay systems Maintain and troubleshoot SMTP mail queues, including resolving latency, backlogs, and mail storms Manage enterprise SMTP routing, relay configurations, and mail flow policies Support SMTP, ESMTP, and related protocols, including secure mail transport via TLS Maintain DNS configurations relevant to email delivery (MX records, routing dependencies) System Administration (Linux/Unix) Install, configure, and maintain Linux-based servers supporting email infrastructure Perform system provisioning, patching, upgrades, and decommissioning activities Ensure high availability and performance of production systems Troubleshoot OS-level and service-level issues impacting messaging platforms Security & Compliance Implement and manage anti-spam, anti-virus, and content filtering controls Ensure secure email transport through TLS encryption and certificate management Enforce enterprise email policies and content control utilizing ProofPoint Services Collaborate with security teams to mitigate vulnerabilities and ensure compliance Automation & Scripting Develop and maintain automation scripts using Bash, Perl, or similar tools Automate operational tasks such as monitoring, log analysis, and maintenance workflows Improve operational efficiency through process optimization and tooling improvements Technical Skills Advanced experience with Linux/Unix system administration Strong expertise in Sendmail and/or Postfix configuration and management In-depth understanding of SMTP and related email protocols (TLS, DNS, IMAP/POP3 fundamentals) Knowledge of networking fundamentals: TCP/IP, DNS, SSL/TLS, SSH Experience with email security controls (anti-spam, anti-virus, content filtering) Proficiency in shell scripting (Bash) and/or Perl Professional Skills Strong troubleshooting and analytical problem-solving skills Ability to manage multiple concurrent tasks in a fast-paced environment High attention to detail and commitment to operational excellence Strong communication and collaboration skills across technical teams Preferred Qualifications Experience with large-scale enterprise messaging environments Familiarity with cloud-based email relay or hybrid architectures (e.g., AWS-based SMTP patterns) Knowledge of directory services (LDAP/Active Directory integration) Experience with Microsoft Exchange or hybrid messaging environments Relevant certifications (e.g., Linux, networking, or messaging platforms) TCP Career Step Differentiator: Performs complex systems administration duties and troubleshooting. Education/Experience: Bachelor’s degree (BS/BA) desired in Computer Science. 3+ years of related experience. Certification is required in some areas. Joining our team comes with amazing perks and benefits: Medical/Dental/Vision coverage 401(k) plan Tuition reimbursement program Paid Time Off and Holidays (at least 23 days of vacation each year and 9 company-designated holidays) Paid Parental Leave Paid Caregiver Leave Additional sick leave beyond what state and local law require may be available but is unprotected Adoption Reimbursement Disability Benefits (short term and long term) Life and Accidental Death Insurance Supplemental benefit programs: critical illness/accident hospital indemnity/group legal Employee Assistance Programs (EAP) Extensive employee wellness programs Employee discounts up to 50% off on eligible AT&T mobility plans and accessories AT&T internet (and fiber where available) and AT&T phone. Weekly Hours: 40 Time Type: Regular Location: Atlanta, Georgia, USA:TX:Dallas / One AT&T Plaza (208 S Akard - Whitacre Tower) - Adm:208 S Akard St Salary Range: $106,100.00 - $178,200.00 It is the policy of AT&T to provide equal employment opportunity (EEO) to all persons regardless of age, color, national origin, citizenship status, physical or mental disability, race, religion, creed, gender, sex, sexual orientation, gender identity and/or expression, genetic information, marital status, status with regard to public assistance, veteran status, or any other characteristic protected by federal, state or local law. In addition, AT&T will provide reasonable accommodations for qualified individuals with disabilities. AT&T is a fair chance employer and does not initiate a background check until an offer is made. #J-18808-Ljbffr AT&T