Rob linux

From ByteWiki

Contents

Reason for this Entry

As i am trying to gain an understanding of Linux during my IBL year i thought it would be a good idea to have a place where i could store all the information that think might be useful in the future. Originally this was a text file on my Ipod which i added to when needed but this became difficult to manage due to the fact that sometimes i forgot to bring my Ipod to work. This meant that i ended up with multipule versions of my file.

As a result it was suggested to me that i create an entry on the byteclub wiki, which as you can see i have done.


The Information

Rotate Logs

Default time for keeping logs is 4 weeks (it was suggested to me that this is quite a short time and it should be increased)

To change edit the rotate parameter in

/etc/logrotate.conf

Enabling DHCP server

To setup a DHCP server on an interface

for a once off use

dhclient ethX should do it.

for a permanent solution edit

edit /etc/sysconfig/network-scripts/ifcfg-ethX.

whatis

To get a short description of a command use

whatis [command]

Finding Files

To find a file use

locate [file_name]

Alternatives (in really bad description)

 find [some/directory or . for current] -name or -iname '*something*'
 find [some/directory or . for current] -atime +n (older then n days, use -n for younger then n)

The locate database updates at 4am in a Cron job. If you manually need to be update the database use

updatedb

ifconfig

Location of ifconfig

/sbin/ifconfig

can be used to show interface info when not logged in as root

ethtool

ethtool gives information about ethernet card settings (can also change settings)

ethtool

Using SCP(Secure Copy Protocol)

scp filename.jpg user@host:/path/to/upload
scp tables.txt rshaw@mercury.it.swin.edu.au:/home/rshaw

needs expansion

Make script executable

chmod +x swu.pl

needs expansion Have a look at the chmod page ;)

SSH login Banner

edit

/etc/ssh/sshd_config

edit Banner to use file e.g.

/tmp/ssh_banner

Example

****Test - rshaw-linux****


Change system HostName

Edit

/etc/sysconfig/network
NETWORKING=yes
HOSTNAME=localhost.localdomain

Running Load Grahps

ssh -X rshaw@venus -f /usr/X11R6/bin/xload

needs expansion

System Services

to update (and query) system service runlevels use

chkconfig 

example

chkconfig named on

Edit IDE Hard disk performance

edit

/etc/sysconfig/harddisks

needs expansion

DVB Notes

Find out your dvb driver module, perhaps dvb-bt8xx or cx88-dvb

add a line to /etc/modprobe.conf alias char-major-212 cx88-dvb

Edit /etc/rc.d/rc.sysinit Find the line other="" and change it to other="char-major-212"

or

make an executable file called /etc/sysconfig/modules/dvb.modules

#!/bin/sh
for i in char-major-212 ;do
        modprobe $i >/dev/null 2>&1
done

The scandata:

T 226500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
T 177500000 7MHz 2/3 NONE QAM64 8k 1/8 NONE
T 191625000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
T 219500000 7MHz 3/4 NONE QAM64 8k 1/16 NONE
T 536500000 7MHz 2/3 NONE QAM64 8k 1/8 NONE

Run svandvb scandata > channels.conf



Installing from Source

Firstly, untar file

tar xvzf dvbstream-0.5.tar.gz

Secondly

./configure <- is this required??

Thirdly

make

Using dvbstream (in Australia)

Download source from http://sourceforge.net/projects/dvbtools/

Extract tar.gz

tar xvzf dvbstream-0.5.tar.gz

Type

make

test by using

./dvbstream

the example below records channel 7 to the file /tmp/test7.mpg for 10 seconds dvbstream -qam 64 -cr 3_4 -gi 16 -bw 7 -tm 8 -f 177500 -ps -n 10 -o 1025 1026 > /tmp/test7.mpg

Where

PID Video = 1025

PID Audio = 1026

Frequency = 177500

Time to record = -n 10

NOT CONFIRMED

FEC = 3_4

QAM = -qam 64

Bandwitch (MHZ) = -bw 7

Transmission Mode = -tm 8

refer http://www.dtvforum.info/lofiversion/index.php/t52.html

Using SMBclient

smbclient /\/\rshaw-linux/\gdm

http://learnlinux.tsf.org.za/courses/build/net-admin/ch08s02.html

smbclient -L 136.186.5.161

Domain=[IT-STUDENTS] OS=[Unix] Server=[Samba 3.0.10-1.4E.6]

       Sharename      Type      Comment
       ---------      ----      -------
       gdm            Disk
       IPC$           IPC       IPC Service (Samba Server)
       ADMIN$         IPC       IPC Service (Samba Server)
       ew101          Printer   ew101
       rshaw          Disk      Home Directories
       Server               Comment
       ---------            -------
       RSHAW-LINUX          Samba Server
       Workgroup            Master
       ---------            -------
       IT-STUDENTS          RSHAW-LINUX


Size of a Directory

use

du -sh 

Free disk space

use

df -h

other examples

uasge of . (hidden) files excluding .. files

du -sh .[^.]*

usage of . (hidden) files as well as viewable files excluding .. files

du -sh .[^.]* *

Create Symbolic Link

use, without the []

ln -s [target directory] ./[shortcut]

IN PROGRESS

Using nmap

Stealth TCP SYN scan - Only sends a SYN packet - referred to as Half Open Scanning

nmap -sS 192.168.0.1

Tries to find what Operating System is running on 192.168.0.1

nmap -O 192.168.0.1


Mount an image on a Loopback device

[root@dalek tmp]# mkdir /mnt/img
[root@dalek tmp]# mount -o loop -t iso9660 dvd.img /mnt/img 

Transcode xvid to DVD - Linux

avimerge -c -o output1.avi -i input1a.avi input2a.avi
ffmpeg -i output-avimerge.avi -target ntsc-dvd -aspect 4:3 DISK1.mpg
dvdauthor -o dvd/ -t DISK1.mpg
mkisofs -dvd-video -o dvd.img dvd/
mkdir /mnt/img
mount -o loop -t iso9660 filename.iso /mnt/img
lxdvdrip -dl=/mnt/img/ -st=vamps
mk isofs -dvd-video -o dvd-finished.img film-dvd/
cdrecord dvd-finished.img

Locations

/media - Removeable media /mnt - System Resources

Burning ISO image

growisofs -dvd-compat -Z /dev/dvd1=FC-5-i386-DVD.iso

This example burned an ISO image to a external DVD Drive (note /dev/dvd1)

Mplayer ASCII

mplayer The\ Chaser\'s\ War\ on\ Everything\ -\ 1x11.pdtv.xvid.buddy.avi -vo caca -ao none -quiet

new

ffmpeg -i doug.avi -pass 1 -target pal-dvd -b 2000 -aspect 16:9 doug.mpg

currently trying approx 2 x original bitrate

Misc

cp -R Kanye\ West\ -\ The\ College\ Dropout/ ~pdealy/Kanye_West

getfattr -R -d /usr/ /var/


Play DVD Image with xine

xine dvd://home/ibl/rshaw/misc/video/pride-fc2006.img

could also be .iso