Senior Systems Administration

• 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

Do you have experience in Vendor relationship management?, Do you have a Bachelor’s degree?, * 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, * 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.

208 South Akard Street, Dallas, TX, $106,100 - $178,200 a year - Full-time, Pulled from the full job description

• Tuition reimbursement
• Paid parental leave
• Parental leave
• 401(k)
• Health insurance
• Paid time off
• Employee discount, Our Senior Systems Administration, earns between $118,800-$178,200 USD Annual, Not to mention all the other amazing rewards that working at AT&T offers. Individual starting salary within this range may depend on geography, experience, expertise, and education/training.

Joining our team comes with amazing perks and benefits:

• Medical/Dental/Vision coverage
• 401(k) plan
• Tuition reimbursement program
• Paid Time Off and Holidays (based on date of hire, 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

Join AT&T and help shape the future of communications and technology that connect the world. We value innovators who seek to explore the unknown and challenge the status quo. Bring your bold ideas and fearless spirit to redefine connectivity and transform how people share stories and experiences. At AT&T, you won’t just imagine the future-you’ll build it.