Samenvatting – Linuxvrouw

BIOS = first step àhardware (clocktime)/separated form OS/what devices and in what order
BIOS reads the bootloader from the MBR (stage 1) , is 2e step
Stage 2 bootloader (LILO—must be informed after changes and GRUB)= load the kernel
Kernel = initializes hardware/loads initrd/create root device/start init
Init = starts all other processes that allow uses of the system à getty: allows users to login
DMESG = bootlog /var/log/messages
Runlevel 0 = shutdown
Runlevel 6 = reboot
2=multiuser 3=network 4 userdefined 5=xmodus
Setting default runlevels = /etc/inittab
Telinit = change runlevel
/etc/init = which programs starts for the various runlevels
/etc/init.d = scripts for starting and stopping daemons
Installing Grub; grub-install /dev/had grub-mkconfig
/bin/bash = editing startmenu

Fdisk provide a frontend for all the commands à making partition
Ext2 / ext3 = journaling
Insmod + modprobe = load a module
RAID can be treated as a partition for mounting à storage data on multiple disks into a LVM, prevent data loss
RAID created = mdadm
Lspci = see the hardware
/etc/fstab = partition listed
SWAP = 2x RAM, when system is out of Ram
Bootloader is located in Bootable
Logical volumes = analogue to partition
Partitions are stored in the MBR, max 4
Boot (static compiled) + Home can have its own partition
Superblocks: metadata

/etc kernels, systemfiles, bootfiles

/dev devices files

/etc configuration files

/lib libraries

/mnt temporay mount

/opt optional applications suites and environments

/proc virtual file system

/root home of root

/tmp temporary file

/home home of the user

/var

/usr usr/home /man helpfiles man format

/info helpfiles info format

/include header files to build programs

/lib applic libraries

/bin application + non-essesentail system binaries

/sbin “ “

Unicode for various differend languages à moving data from one encoding to another
ASCII + UTF -8 for Unicode
Iconv = another type of conversion
LANG LC_* LC_ALL = whicj language
Locale is set by environmental variables; local –a = what locals are available
/etc/localtime
Tzselect = change timezone
Tzconfig = change settings
Hardware time = bios
Systemtime = date
NTPD = set at server time
Sntp = keep a system’s time automated and very precize
New user = adduser
At = command in the future at –f = file
Atq = managing at commands atrm = cancel commands
CRON = program that performs tasks at regular intervals, bv backups
Minute hour day month dayoftheweek
Date = system clock
NTP = clocks synchronized
allow + at.deny = neither
Usermod = alter various aspects
Chage = change password every so often
/etc/shadow
Username;password;user id;group id;comments about user;userhome
Disable account = lock an account

com/blog/entry2415.html
conf = change settings
Programming languages apache = required apache modules
“C” associated with kernel
Python = whitespace
Update = to alter data
Insert = create new data
Delete = remove data
Select = return data
SQL = structure query language, communicatie with relational databases
LAMP = requires server (as a daemon) – finding a way to get data in and out of a database – using CLI or GUI
Start mysql server – set it appropriate runlevel – create user
CREATE DATABASE – USE – CREATE TABLE
INSERT = add rows
UPDATE = edit data
DELETE = remove
SELECT = output values
* display all colums
WHERE = defines the rows
Languages: Perl – Python – C (gcc = gnu C compiler) – C++ – PHP