linux crash course chapter 02 3

Logging on• Your username will be your My.Solano username • Your password is by default set to your SCC ID, all 9 digits pad front with zeroes • *Remember* Linux/Unix is case sensitive..

Chapter 2:

Getting Started

Logon to Logout

Consoles and terminals

• Monitor, keyboard (and maybe mouse) attached

to the box

• The console often locked away in a closet or

server farm somewhere

• Terminals usually found in mainframe

environment

• Recently ‘thin clients’ gaining popularity again

From Windows environment

• telnet built in, but insecure (cleartext passwords)

• For ssh, need a supported terminal emulator

– PuTTY, TeraTerm Pro, SecureCRT

• For remote X Windows, need a local X Server running

– cygwin, XWin-32, Exceed, Xming

Here at Solano College

• Our server is racked in the campus MDF

• RedHat Enterprise Linux 5 virtualized on Vmware ESX

• We’ll use PuTTY and cygwin

Logging on

• Your username will be your My.Solano username

• Your password is by default set to your SCC ID, all 9 digits (pad front with zeroes)

• *Remember* Linux/Unix is case sensitive

Change your password first

• To secure your account, change your password immediately

• Type passwd and hit enter

• You will be prompted to enter your current

password

• You will be prompted twice for a nice password

• Must be a good password!

What Makes a Good Password?

• At least 6 characters long (8+ is even better)

• Not be a dictionary word in any language

(including Klingon!)

• Not a name, place or date of personal significance

• Contains mixed case, numbers, and special

characters

Do It Right!

• bfd  BAD PASSWORD: it’s WAY too short

• bfd*2  BAD PASSWORD: it is too short

• 123454321  BAD PASSWORD: it is too

simplistic/systematic

• shutup!  BAD PASSWORD: it is based on a

dictionary word

The Shell

• Command interpreter

• Translates commands issued by user into commands sent to the kernel

• Common shells: bash, tcsh, csh, zsh, ksh

• Linux default is bash (Bourne Again Shell)

What shell am I running?

• Type ps right after logging on

• finger yourself

Other key commands

• Terminate (interrupt key): CTRL-C

• Suspend job: CTRL-Z

• Show jobs: jobs

• Stop job: kill –KILL %job_no

• Command history: UP and DOWN

Administrative privileges

• root or superuser

• Full read/write access to filesystem

• Can execute privileged commands and programs

• Use sparingly and with extreme caution

Getting help

• Most GNU commands and utilities have built in help and usage information

• help (sometimes -h or -help)

• Too much information? Pipe results to less or

more

– ls help | less

man Pages

• man program_name

• Displays online documentation, formatted with a pager

• SPACE to advance, q to quit

• Depending on the system sometimes you can also

use PAGE UP/DOWN

man Pages con’t

• Divided into ten sections based on type

• User commands in section 1

• To view a command’s man page in a particular section:

– man 8 su

At the end of the day

• To log out, press CTRL-D or type exit

• If you have suspended jobs it will warn you before you log out