What are the concepts required for a system administrator?

As I am not much technically skilled for IT solutions but through the experience, I have gained the knowledge that it all depending upon your workstation tasks and KPIs. If you seek specific response then question must be specific too.

Thanks for the call, please clarify the question any meaning system

A Linux based system administrator should have the following skills as :

• Understand and use essential tools for handling files, directories, command-line environments, and documentation
• Operate running systems, including booting into different run levels, identifying processes, starting and stopping virtual machines, and controlling services
• Configure local storage using partitions and logical volumes
• Create and configure file systems and file system attributes, such as permissions, encryption, access control lists, and network file systems
• Deploy, configure, and maintain systems, including software installation, update, and core services
• Manage users and groups, including use of a centralized directory for authentication
• Manage security, including basic firewall and SELinux configuration
• Configuring static routes, packet filtering, and network address translation
• Setting kernel runtime parameters
• Configuring an Internet Small Computer System Interface (iSCSI) initiator
• Producing and delivering reports on system utilization
• Using shell scripting to automate system maintenance tasks
• Configuring system logging, including remote logging
• Configuring a system to provide networking services, including HTTP/HTTPS, File Transfer Protocol (FTP), network file system (NFS), server message block (SMB), Simple Mail Transfer Protocol (SMTP), secure shell (SSH) and Network Time Protocol (NTP)

Thank you for the invitation.

• Planning - cost, capacity planning, logistics (network design, server locations, where to install, wiring, IP address assignments, ...), network service providers (ISPs)
• Preparing - temperature, humidity, electrical, fire, security, EIA/TIA wiring closet and cabling standards, UPS; Change management (preparing for any service changes)
• Installing hardware - computers, terminals, disk drives, CD-ROMs, RAM, printers, NICs, cabling
• Maintaining - regular preventative maintenance (daily, weekly, ...), boot and shutdown systems when needed, printers, backup media, tune systems for performance
• Monitoring - printers, disk space, network, servers and workstations, performance, and security, and all log files regularly
• Installing/upgrading/removing software - OS (kernel patches, new device drivers, ...), applications (new versions, DLLs, new configurations), documentation
• Backups and archives
• Configuring - kernel, networking software such as Samba, X Window, accounting, quotas, security, mail, news, time, web and other servers, ...
• Trouble-shooting - network connections, services that don't start, faulty security, ...
• Maintaining local documentation - new user's guide, policy and procedure documents (security plan, disaster recovery plan, administrative procedures, service request/bug report forms, ...), man pages for add-on software
• Help and educate users - This includes working with your management (who sometimes needs the most help and education even if they don't think so), helping new users, experienced users, and yourself
• Baselining - Generate system reports and correlate growth, changes over time.  (Use data to order supplies, spares, hardware and software upgrades in a timely manner, and to generate reports to management)
• Problem solving - System administration is about solving problems, not memorizing how-to directions.  Often something won't work as it should.  What will you do then?
• Know where to look for help - books, Netnews, man pages, on-line (www.tldp.org, docs.sun.com, www.redhat.com, ...)

I agree with MR Sameer . question not clear

Agree With answer given by Mr. Vaiyapuri Gopalakrishnan