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Jr. System Administrator

Leidos · O'Fallon, IL · $50,700–$91,650 a year · Full time

Posted Sep 24, 2026 · We last checked this listing on Oct 6, 2026

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Likely interview questions for this role

Written from this job description, not a generic list. Each one notes what the interviewer is really checking.

About your past

Tell me about a time in a customer service job when you dealt with a frustrated person.

What they are checking: Whether they can stay patient and helpful, drawing on the customer service experience the posting requires.

How do you keep tickets updated so your team and the customer know where things stand?

What they are checking: Whether they see ticket updates as communication, which keeps ongoing efforts visible.

Tell me about a time you worked independently on a technical problem with little guidance.

What they are checking: Whether they can work on their own, which the posting lists first among the duties.

How are you building your technical skills right now, outside of work or school?

What they are checking: Whether they are actively growing, which matters in an early-career role with less than two years of experience.

What would you do

A user asks you to give them admin rights so they can install software. How do you respond?

What they are checking: Whether they explain and enforce security policy politely, since protecting DISA systems is the core of the role.

An alarm goes off on a monitoring tool and you are not sure what it means. What do you do?

What they are checking: Whether they investigate calmly and escalate when unsure instead of ignoring or guessing.

This role includes on-call, extended hours and weekend support when the mission needs it. How does that fit your life?

What they are checking: Whether they can truly be available when emergencies happen outside business hours.

If you were asked to evaluate a vendor product, how would you decide whether it fits our environment?

What they are checking: Whether they think about security, compatibility and support rather than just features.

About the work

Walk me through how you would troubleshoot a user who suddenly cannot log in to a shared system.

What they are checking: Whether they follow a logical path through accounts, permissions and network before guessing at fixes.

What basic system administration tasks have you done on Windows or Linux, and which are you most comfortable with?

What they are checking: Whether their hands-on skills match the basic sysadmin duties this role starts with.

How would you write a standard operating procedure so someone new could follow it without asking you?

What they are checking: Whether they write clear, step-by-step documentation, which this role creates and maintains.

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The full job description

As published by Leidos.

Leidos is seeking a candidate to fill a Junior System Administration position supporting DISA's GSM-O contract at Scott AFB, IL. The System Administrator is responsible for protecting DISA’s information and information systems from unauthorized access, use, disclosure, disruption, modification, perusal, inspection, recording and destruction. PRIMARY RESPONSIBILITIES: • The candidate must be able to work independently to maintain the smooth operation of a multi-user computer systems, including coordination with customer and other administrators. • Communicate policies and procedures to customers • Update digital systems to provide insight to ongoing efforts and tickets • Monitor alarm systems • Perform basic level system administrator duties. • Interacts with users and evaluates vendor products. • Creates, maintains, and implements detailed documentation and maintains standard operating procedures. • Provides support on a M-F business hours schedule, also responsible for on-call, extended hour, and weekend support as required by mission or emergency situations. • System monitoring using installed tools as well as external tools. BASIC QUALIFICATIONS: • BA Degree and less than 2 years of experience. Experience may be accepted in lieu of degree. • 1 year of experience in customer service environment • Must hold an active SECRET security clearance prior to start. • Complete DoD 8750 certification e.g. Security+ within 6 months of start date. • Basic Understanding of Scripting Languages PREFERRED QUALIFICATIONS: • Additional training, education, or certification in IT related programs • Experience with a ticketing system • Experience working with virtual environments. GSMO If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares. Original Posting: September 24, 2026 For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above. Pay Range: Pay Range $50,700.00 - $91,650.00 The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.

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