Table of Contents Previous Chapter Introduction.
- Please take a moment to fill out this survey form to help identify the audience for this course (only those actually in the classroom can do this).
Noun:
- One who administers; one who manages, carries on, or directs the affairs of any establishment or institution.
- One who has the faculty of managing or organizing.
- One who executes or performs the official duties of religion, justice, etc.; one who dispenses or ministers to the public in such matters.
- One to whom authority is given to manage estates, etc. for the legal owner during his minority, incapacity, etc.; a trustee, a steward. esp. in Sc. Law. `A person legally empowered to act for another whom the law presumes incapable of acting for himself' (Encyc.Brit.), as the father of children under age.
The bottom line: Administration of a Unix system on the Internet -- or any other system, for that matter -- is a full-time responsibility, not a part-time, casual activity.
- Performing backups
- Adding and removing users
- Adding and removing hardware
- Restoring files from backups that users have accidentally deleted
- Installing new software
- Answering users' questions
- Monitoring system activity, disc use and log files
- Figuring out why a program has stopped working since yesterday, even though the user didn't change anything; honest!
- Monitoring system security
- Adding new systems to the network
- Talking with vendors to determine if a problem is yours or theirs, and getting them to fix it when it is their problem
- Figuring out why "the network" (or "Pine", or "the computer") is so slow
- Trying to free up disc space
- Rebooting the system after a crash (usually happens when you are at home or have to catch a bus)
- Writing scripts to automate as many of the above tasks as possible
- root (a.k.a. "super user"--guard this account!)
- everybody else
- Log in as root from the system console (avoid)
- Use "/bin/su -" command from your regular account (better method)
- $HOME is / (Watch what you delete!)
- Change the password frequently and use "good" passwords (more on this later)
- Remove the current working directory (a.k.a., ".") from your PATH
- Never leave the terminal unattended, even for "just a minute"
- Limit who has the root password to as few people as possible
- Never execute any regular user's program as root (possible Trojan Horse)
- Never let anyone else run a command as root, even if you are watching them
- You risk having your password stolen by "sniffers" if you use programs like "telnet", "ftp", access email remotely with POP/IMAP (anything protocol involving "clear-text" passwords)
- Install RedHat Linux from an NFS server
- Set up a user account
- Configure "tcp wrappers" for UW-only access
- Set up syslog to consolidate some log entries on a central server
- NFS mount the RedHat distribution archive and load RPM packages directly
- Review the RedHat errata sheet and update RPM packages via ftp.
- Perform a backup of /etc to floppy and recover a backed up file
- Shut the system down and restart it in single user mode
- Change the system startup default to use XDM
- Download and install the Secure Shell (SSH)
- Modify the system startup to start the Secure Shell daemon on boot
- Investigate a security incident
Table of Contents Next Chapter