Lesson 1: Understanding Server Administration Concepts

System Administrators

Manage server and network hardware, lifecycles, documentation, and security. Primary skill is problem solving.

Responsibilities of System Admin

• Installing, configuring, and managing hardware, apps, and network components.

• Monitoring performance

• Troubleshooting

• Managing lifecycle

• Collaborating with IT teams

• Monitoring performance

• Resolving complex tech issues

• Capacity planning

• Managing different technologies and network services

• Providing documentation

• Improving communication and presentation skills

• Advising on adding security policies

Workstation

• Assigned to end user

• No redundant hardware

• No high performance hardware

• Client OS(single user)

• Elegant GUI

• Desktop/laptop form factor

• Apps for one user

Server

• Secured in a server room

• Redundant hardware

• High performance hardware

• Server OS for many users

• Apps for multiple users

• Limited/no GUI

• Rack mounted

Workstation OS

• Ubuntu desktop Linux

• Mac OS

• Microsoft Windows 10

Server OS

• Red Hat Enterprise Linux 8

• Microsoft Windows Server 2019

Server Lifecycle

Procurement, Usage, End of Life, Disposal and Recycling

Four Major Subsystems

Processor, Memory, Storage, Network

Processor

Amount of processing power the system has available

Memory

Storage capacity available to the CPU for quick access to data

Storage

Storage capacity and access speeds available for the OS and user data

Network

Capacity for sending and receiving information across the network

Linux

Open source and free, each distribution is purpose specific. Like RHEL is to be used in large scale business development. Can be modified and then redistributed.

Branches of Linux family distributions

• RHEL: RPM package, used in corporate and enterprise environments. Has paid commercial support. RHEL, Fedora, CentOS.

• Debian: More common w/ developers and general use. Free community support available. Debian, Ubuntu, Kali.

Windows Server

Closes source and commercial. Source code is not allowed to be modified or redistributed. Must be purchased from Microsoft or authorized sellers. Broader driver and software support.

Troubleshooting Methodology

• Identify problem

• Determine scope of problem

• Establish theory of probable cause

• Test theory to determine cause

• Establish plan of action

• Implement/escalate solution

• Verify system functionality

• Implement preventative measures

• Perform root cause analysis

• Document findings, Actions, and Outcomes

Identify the problem

Could be found through end users, support, exposed log files, indicated lights on server, monitoring software, etc.

Determine the scope of the problem

Find what was happing before the issue, backup data if needed, see if you have the ability to fix it. See if the issue is just on one server of every server.

Establish theory of probable cause

Find what probably caused the problem. Begin by looking at the most obvious fixes first.

Test theory to determine cause

Testing to see if what you think what the issue is, actually is. If right move to next phase if not find another theory and test it.

Establish Plan of Action

Figure out how you can address the issue and avoid downtime and using data. If you need to shot down the server let the users know beforehand and how long it’ll be down for.

Implement/Escalate Situation

Follow the plan exactly and be sure to not change it or else it’ll be too hard to evaluate it.

Verify Full System functionality

See if everything works after fix and see if it performs at service levels.

Implement Preventative Measures

Take steps to avoid problem of occurring again and add tech to prevent future failures.

Perform Root Cause Analysis

Figure out why this even happened in the first place and use it to change process and implement tech to avoid the issue.

Document Findings, Actions, and Outcomes

What went wrong, what you tried, and what did/didn’t work.

Software License

Legal contract that governs the distribution and use of software. Tells you how many installations are allowed and how many ppl can use it at once.

Two Different Licensing Structures

FOSS and Proprietary

FOSS Licensing

Free to use, modify, and rerelease software voluntarily to improve the software.

Proprietary Licensing

Where the source code is hidden and users are not allowed to freely modify and rerelease the software. Usually costs money to buy and can be volume and subscription based.