Linux-oefening

1
Linux-oefening
Operationele Aspecten van Besturingssystemen Pro
f. Koen De Bosschere ir. Ronny Blomme
2
Overzicht

• Doelstelling van deze oefening
• Installatie van Linux
• Beheer van Linux
• Oefening in de PC-klas

3
Doel van deze oefening

• Besturingssystemen in de praktijk
• Systeembeheer
• Unix vs Windows
• Gebruik makend van VMware

4
Voorbereiding

• Hardware Compatibility List
• Free Disk space?
• Workstation 2 GB
• Server 2.1 GB
• Personal desktop 1.5 GB
• Custom 400MB tot 4.5 GB

5
VMware

• Intel vs AMD processor
• PCklas B Persistent disk
• PCklas A Non-persistent disk
• NAT

6
Installatiemethode

• Bootable CDROM
• Bootfloppy CDROM
• Bootfloppy netwerk (nfs, ftp, http)
• Unattended kickstart
• Linux Customization Guide

7
Disk-Partities

• fdisk / disk druid
• Partition Fields
• Device /dev/sda1
• Size 110 MB
• Type ext3
• Mount Point /boot

8
Filesystem Type

• ext2
• ext3
• software RAID
• swap
• VFAT Windows 95/NT (long filenames)

9
Filesystem structure

• /dev /etc /lib
• /mnt /opt /proc
• /sbin /usr /var
• /home

10
Boot Loader

• LILO / GRUB
• The master boot record (MBR)
• The MBR is a special area on your hard drive that
  is automatically loaded by your computer's BIOS,
  and is the earliest point at which the boot
  loader can take control of the boot process.
• The first sector of your root partition
• Recommended if you are already using another boot
  loader on your system / NT bootloader

11
Firewall iptables

• packetfilter

Internet
12
NIS domain

• vergelijk Active Directory
• database van network-resources
• Master/slave servers - replication
• LDAP (lightweight directory access protocol)

13
Accounts

• root vergelijk Administrator
• standard users bin adm nobody ...
• users user private group (UPG) scheme
• /etc/passwd uid, gid
• /etc/shadow encrypted password
• /etc/group (vs logingroup)

14
Home directory / Profile

• info in /etc/passwd
• /home/ltusernamegt (op fileserver?)
• Profiel
• displaygebonden profiel (vs roaming)
• onder homedirectory (vs afzonderlijke
  profiledirectory)
• /.kde en /Desktop

15
Permissions

• user, group, others (ugo)
• files read, write, execute (rwx)
• directories xbrowse, wcreate/delete
• UPG scheme (RedHat)
• User Private Group
• umask 002 (urw-, grw-, or--)
• setgid bit on group-directories

16
Boot-sequentie

• BIOS (ROM)
• MBR load the bootloader (LILO)
• /etc/lilo.conf boot linux kernel
  /boot/vmlinuz-ltversiongt
• start the init process
• /etc/rc.d/rc.sysinit
• /etc/inittab
• /etc/rc.d/init.d bootscripts

17
Run Levels /etc/inittab

• 0 Halt
• 1 Single-user mode
• 2 Not used (user-definable)
• 3 Full multi-user mode
• 4 Not used (user-definable)
• 5 Full multi-user mode (with an X-based login
  screen)
• 6 Reboot

18
Bootscripts

• Bijvoorbeeld runlevel 5 /etc/rc.d/rc5.d
• K01pppoe -gt ../init.d/pppoe
• K05innd -gt ../init.d/innd
• K10ntpd -gt ../init.d/ntpd
• K15httpd -gt ../init.d/httpd
• ...
• S05kudzu -gt ../init.d/kudzu
• S06reconfig -gt ../init.d/reconfig
• S08ipchains -gt ../init.d/ipchains
• S10network -gt ../init.d/network
• ...

19
RedHat Package management

• rpm commando

20
Process management

• ps (pid, ppid)
• top
• kill
• renice (scheduling priority)

21
Niet in deze oefening...

• NFS / SAMBA
• SSH / Kerberos
• Automated tasks cron
• BIND / Sendmail
• Webserver Apache
• Kernel-configuratie
• ...