Systems Administration Lifecycle

     * To keep the systems running.
     * To plan and implement upgrades and new services.
     * To plan for disaster, minimising the risk and the potential damage, including backups and disaster recovery planning.
     * To resolve any systems problems that crop up or, better yet, to see the warning signs and head them off before they become a problem.
     * To keep my skills up-to-date.
     * To be a knowledge resource for the company.


Installation
- Hardware Requirements
- Installation methods
- Disk configuration (SCSI, IDE, SATA)
- Host Table
- Networking
- starting and stopping services
- system run levels

Software and Patch administration
- Package Information
- Adding Packages/Packages via Scripts or the Command Line
- Removing Packages
- Displaying installed Packages/Patches

Managing Users
- The /etc/passwd ; /etc/shadow File ; /etc/group files (/etc/skel and bashrc or profile)
- using command line tools or GUI - or manual using vi
- archiving removed users

System Security
- password security (shadow, crack, aging, etc.)
- ssh configuration
- log files - failed attempts, system access via network
- sudoers  (visudo  or vi /etc/sudoers)
- chown, chmod and permissions
- disallowing ftp, or using vsftp

System Service and/or INIT files
/etc/inittab or related to show run level
- /etc/init.d  (rc5.d)
- /etc/systemd

Boot Process
/boot  grub.cfg menu.lst and other related files

File Systems, Disks and Directory Structure
- /dev Device drivers
- mount, umount and /etc/fstab (mount points and drives)
- partitions, fdisk, fsck, du, df, parted
- LVM - volume groups, physical volumes, logical volumes
- dd, rsync, tar, dump, zip, compress, and backups
- NFS, samba
- swap and virtual filesystems
- RAID (0, 1, 1/0, 5)

Administering Processes
- ps, top, kill, xkill
- vmstat, iostat, netstat
- crontab, at and nohup
- /run, /proc and other directories representing processes
- log files

Backup and Recovery
- Full and Incremental Backups
- Tape Devices, SANS, filesystem snaps, rsync

Networking
- ifconfig, netstat, route
- ssh, scp, ftp, telnet and "r" commands
- Printing
- xinetd and inetd
- /etc/hosts, /etc/resolv.conf, /etc/nsswitch.conf
- NIS, LDAP, MS_DNS, DNS, DHCP and other network services

Shell Scripting (cron, at)
- Comments, echo, variable declaration, loops, if, while, case



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