catatan seorang administrator

struktur hierarchy linux.

/boot

linux kernel. grub bootloader.
isolasi kernel dari file biasa.


/home

buat backup biar lebih mudah
supports quota for user


/media , /mnt

standart buat removable drives



/tmp
buat sharing. essential for gui logins





/var
log files.


=======================

ps

ps a

ps -u toro
ps -u 1000   (1000=id   dapat dilihat pada /etc/passwd)

ps -aux   -> smuanya

pstree


iostat



kill -1 /usr/sbin/smbd   = restart smbd
kill -9 /usr/sbin/smbd   = matikan


highest priority  = -20
lowest            = 19

start new process, priority=-10

nice --10 process  atau
nice -n -10 newprocess


renice -13 pid          //repriotize


cp /etc/passwd .  = mengopy ke local directory

======================================
vi ->   hjkl     h kiri l kanan


u  > undo
dd > delete 1 baris
dw > delet 1 word

yy trus p  >  masukin baris ke buffer trus paste


:! = execute mode

:w new_file_name


==========================================


file *   = ls

file /boot = ls /boot

find . -name "*.doc"  =   cari di local directory yang bernama x.doc
find / -name "*.doc"  =   cari di root directory yang bernama x.doc


ls -F               *= executable, @= symbolic, = = socket, | = pipes


mkdir -p /path/to/dir  = lgsung bikin directory 3 bijiq


ctrl+alt+f1   =  tty 1
ctrl+alt+f2   =  tty 2

=========================================

rpm -q  packages= liat nama packages
rpm -qi packages = liat informasi lanjut package
rpm -ql packages = list file didalem packages
rpm -qa = melihat list seluruh packages

rpm -i xxxx.rpm =  install packages rpm
rpm -ql xxx.rpm =  melihat isi list didalemyna

rpm -ivh   =  verbose(lebih lengkap/showing process)  and h =  see the bar process.


rpm -U packagename = upgrade / install
rpm -F packagename = upgrade if only older version installed

rpm terkadang butuh dependencies -> pake yum (yellowdog updater,modifier)



tar.gz        gzip -d
tar.bz2       bzip2 -d

trus d tar

atau

tar xzf  = untuk tar.gz,  gzip
tar xjf  = untuk bz2,     bzip



======================
fdisk -l   > list partition

fdisk /dev/sda

parted /dev/sda print   > ati2. lgsung write tanpa confirmation


mkfs          >   format partition/volume/array

mkfs.ext2,mkfs.ext3, mkfs.ntfs, mkfs.msdos, mkfs.vfat,mkfs.reiserfs



==========

raid 0 = striped

data distributed over multiple partition.
failure in any disk/partition = lose all data

raid 1 = mirror

identical copies of data written to two partition
a bit slower

raid4 = ?

raid5 =  3 / lebih partisi
distribusi parity bits
data survives failure of one component


raid6 = 4 / lebih partisi
2 levels of distributed parity
data survives failuer of components

raid 10 = raid 1+0    (kombinasi)



command=       mdadm /dev/md0

========================

mount -t nfs 192.168.0.50:/backups /test/        -> mount dr network digabungin sama cron buat backup bisa.

mount -t cifs //192.168.0.50/backups /microsoft/           -> mount file sharing microsoft

unmount test/


=====================
grub.conf = redhat

menu.lst = debian






title = judul
default=0      -> first stanza
root (hd0,0)     ->first drive, first partition
root (hd0,1)     -> first drive , second partition

kernel /vmlinuz-xxxxx.e15           ro  root =/dev/x/x    ->  ro read kernel read only

ro quiet splash            ->


initrd /initrd-xxxx.img         -> initial ramdisk


=================


grub-install /dev/hda  = first pata drive
grub-install /dev/sda  =  first SATA / scsi drive



================
list loaded driver=lsmod


 /etc/modules.conf
 /etc/modules
 /etc/modprobe

insmod =>   load modules without dependant
modprobe => load modules + dependant



==============

echo $PS1  => default cmd
echo $PS2   =>  prompt for incomplete command

echo $PATH


crontab -e



==============



/dev/null = trash bin , auto discarded    -> bisa digunakan sbagai penghapus otomatis spam email



major minor patch bugfix =  2.6.30.5


==============

apropos passwd => command2 passwd   // man -k passwd

man 5 passwd => manual page 5

info passwd

/usr/share/doc        => smua ada disini documentation software



==============

make clean         >  Cleans source code

make dep           >  connects dependencies

make               >  compiles src code

make install       > process for installation


============

apt-get  >  acquire download install

apt-cache  search name > search through repos

apt-get purge [filename]  > delete package dependencies config files

apt-get update        > install available update



============

lsusb   >  conencted usb devices

lspci   >  connected internal hardware

lspcmcia  > connected pc card


check  /sys , /proc ,  /proc/usbinfo   !?