CMPE 151: Network Administration

Spring 2004

Class Description Focus: system and network

administration. Sequence of exercises.

E.g., installing/configuring client machines (including kernel), servers (FTP, Web, file server, mail, DNS, etc.), network gateways (firewalls, NAT), etc.

Final project.

Class Format Lectures.

Meet in BE 168. Typically, 2 lectures on each topic:

A more “theoretical” lecture on background material.

A more “practical” lecture to get projects started.

Lab time. Students expected to spend ~10

hr/week in the lab.

More class information Grading:

Weekly projects: 75%. Final project: 25%.

Academic Integrity Policies: Will be strictly enforced. Come talk to us if questions.

Class Web Page www.cse.ucsc.edu/classes/cmpe151/Spring04. One of the main course resources. It will be constantly updated. Students are responsible for

keeping track of updates (e.g., syllabus, project due dates, links to project descriptions, etc.).

Projects Current list and due dates on Web

page. Project description.

Should have all information required for each project,

Including how to submit project. They will be added as we go.

Readings and Documentation List of recommended books on the

Web page. Links to on-line documentation.

Documentation provided on the Web page as starting point.

Seeking further documentation to complete an assignment is considered part of the assignment.

Lab Usage Policies Very important! This is our lab and we must keep it

in working condition!

Lab Usage Policies (cont’d) Access:

Only to registered students! No food or drinks!

Equipment: All equipment must remain in the lab at all times. Students are responsible ($$$) for faulty, stolen,

vandalized equipment. Students must report immediately any problems.

Lab Fee: Used for printing and some “non-

permanent”equipment.

Lab Setup LAN of workstations. Connected to outside world through netlab.cse.ucsc.edu.

All students will get an account on netlab.cse.ucsc.edu.

Students will have root access on all other machines. After finished using a machine for the day,

students must restore them to their original state.

UNIX Basics

Brief history Originally developed at AT&T Labs in

the late 60’s. In the mid 70’s, UNIX was made

available to universities and research centers free of charge.

In 1977, Berkeley’s UNIX distribution became available: BSD (Berkeley Software Distribution). Final release: 4.4BSD-Lite. FreeBSD originates from this release.

UNIX structure

Hardware

UNIX Kernel

Shell

Utilities: editors, compilers, etc.

Shell Command interpreter. Interface between user and OS. Several shells: bourne shell, C

shell, bash, etc.

File structure Unix file systems are organized as

hierarchies of files and directories.

File structure: example

Client/root

vmunix usr

staffstudents

Server 1/root

export

users

joe bob

Server 2/root

nfs

users

ann eve

Files and directories Files are leaf nodes in the file

structure tree and directories are intermediate nodes.

File names: up to 255 characters. Upper and lower case letters. Numbers. Some special characters. File name extensions (preceded by

“.”). Describes file content.

Pathname Concatenation of directory names

from root to file name using “/” as delimiters. Example: /export/users/bob /cse/faculty/katia

Absolute versus relative pathnames.

Special directories Working directory (or “current”

directory): “.” Home directory (“~”). Parent directory: “..”

Navigating… pwd. cd. ls.

Creating and removing directories mkdir. rmdir.

Moving and copying mv. cp. Example:

$ pwd/home/katia$ mv summary.txt documents/.

Access permissions Types of permissions:

Read, write, execute. Who can do it?

Owner, member of owner’s group, anyone else.

ls –l (long) displays access permissions, file owner and group, size, last modified data and time, file name.

Changing access permissions chmod Example:

chmod a+rw summary.txt

Listing file contents More, cat, less.

Shell Command interpreter. Command line. Shell script.

Command line Syntax

<command> arg1 arg2 … argn [cr] Execution:

If shell finds file with same name as command, a new process is started to execute that file.

Shell is sleeping while command executes.

Shell returns to active and issues prompt.

Standard input and output Default places where input info is

read and output info is sent. By default, stdio and stdout is the

terminal.

Redirection Redirect stdin and stdout. <command> [arguments] > filename <command> [arguments] < filename Example:

$ cat summary.txt $ cat summary.txt > summary2.txt $ cat > sample.txt

Pipes stdout of one command “piped” to

stdin of anther command. Example:

cat summary.txt | more who | grep “katia”

Running program on background OS runs program while you can do

other things. “&”.