Linux stuff

[mikayd]

Hey I just thought it was time we compare knowledge with each other on linux i dont know much but what i learnd in school but hey ill start it off i hope some one reply

RPm Packages – Rpm -1 package-1.2.3-4 i386 rpm … is the most basic syntax for installing an rpm

Gnome Rpm is a graphical Gnome tool that makes installing Rpm Programs Quick and easy clicks.

Kpackage is an application used for maintaining rpm software packages on your linux system.

Debian a debian package, like rpm package, contains all the files necessary to intall a program or a suite of programs

Dpkg –intall
-unpack
-configure
-fsys-tarfile
-remove
-purge
-list

Apt is used to manage packages in such a way that when the user asks for a package to be installed the sytem also installs ( or upgrades ) all the necessary packages to make the package work Debian based systems include a file, typically /etc/Apt/sourses.list

Apt-get update
Check
Install some package
Upgrade checks for outdated Packages in the system and automatically upgrades them
Dist-upgrade
Remove some package
Clean, removes all files


Common Gzip and tar extensions

.z - Compress/uncompress. Use uncompress frame foo.z to uncompress the file, where fname is the name of the file that was uncompressed.

.Z, .Gz or gzip – gzip is now used by many archive sites instead of compress. If you don’t have gzip on your system. Get it! To uncompress one of these files, use gzip –d fname.z is the new gzip extension

.tar – tar file. Use tar xvf fname.tar to unpack it. Or you can use tar tvf fname.tar to get an index listing of the tar file.

.Taz Compressed tar file. You can do something such as zcat fname.taz _ tar xvf – or tar xvfz fname to unpack it. Some version of tar don’t use the z option)

.tpz, .tgz gzipped tar file. If you have gzip, zcat is linked to it, so you can do zcat foo.tpz | tar xvf to upack it


.tpz - the old extension. All gzipped tar files should now end in .tgz instead.

To create an tar file …. ( tar -cvf filename.tar files/directories )


Ps – displays processes you as a user own .

Ps –a – displays all process running

Top – displays process running in realtime is an interactive version of the ps command

Init – process by process Id

Kill – kills process by process Id .

Kill -9 – sigkill – forces init to immediately destroy it

Kill -15 – sisterm – gives the process a chance to clean itself up before closing

Killall – Terminate Process by name and not pid

Rpm – ( Example rpm-I packagename.rpm)

-I = install
-u = upgrade
-e = remove
-v = verify
-q = see if package is installed
-urpmi = lists the dependencies

Debian- dpkg –I packagename.deb

-info = prints out the control file
-I or install = install a package
-unpack = unpacks but dose not configure
-configure = configures a package that already has been unpacked
-Remove = removes a packages
-purge = removes a package including its config files
-list = lists the installation status
Gzip – gzip filename.ext – zip a file
- gunzip filename.ext – unzip a file

Tarballs – tar cvf filename.tar files/ dorectorires

-c = create tar file
-v = verbose mode, displays output
-f = copies files into tar file created
-z = zip the tar file after creation
-x = extract, un-tar the file
- t = view what in tar file

Ipr Process – the lpr ( is short for line printer ) Program is the only program in linux that queues print jobs. All other programs that need to print files do so by sending the data to lpr. When lpr runs. It gathers information about the print jobs from three sources:

* Command line options used with the lpr command
* Enviroment variables, such as Printer, that identify the printer where the output is to appear
* System defaults that provide information that lpr needs, such as the default printer name (lp)

Lpd, short for line printer daemon, was used in the original bsd unix and has been the standardon unix for years as a basic print spooler.

Note : the lpd is also the name given to the network printing protocol used in tcp/ip printing. It takes care of actual printing – act of spending a file to the printer. A copy of ipd is always running in the system.

You can Check for existence of the lpd program with the following command

Ps ax | grep lpd

Spool direcorty the spool directory is where data destined for a printer accumulates in separate files before the lpd printer daemon sends those file to the printer.

Lprng is a print spooling system,

Print cap the /etc/printcap is at the heart of linux’s printing environment.


Sending a file to the printer at the command Prmpt

Example Lpr file1.txt

If you have a printer connected to the /dev/lpr parallel port, you can print a text file simply by sending the file totthe printer with the following command.

Managing the printer and print Queue from the command prompt

All users can use the lpc status command to check the status of partners . If you log in as root, you can use lpc to perform many more printer controls functions, such as starting and stopping spooling, enableing and disableing printers, and rearranging the order of print jobs. You can use the second argument to lpc to perform a specic task or run lpc in interactive mode .

To see the name of the default (lp0) that is connected to your system, use the lpc status command. To see all printers , you would use the lpc status all. As you can see from figure 8.9 the screen will show if the printing you


Ifconfig

( Example Ifconfig device Ip_address options )

Up = Enables the device
Down = disables the device
Arp = enables this device to anwer arp requests.
-Arp = Diables the device from answering arp requests.

Mtu value Sets the maxium transmission unit (MTU) of the deivce to vaule. Under Ethernet, this defaults to 1500.

Netmask mask sets the subnetmask to the interface to mask. If a value is not supplied, ifconfig calculates the netmask of 255.0.0.0 Class bgets 255.255.0.0, and class c gets 255.255.255.0

Broasdcast bcast sets the broadcast address to this interface to bcast. If a value is not supplied ifconfig calculates the broadcast address based on the class of the ip address in a similar manner to netmask.

Pointtopoint ppp_address Sets up a point-topoint (ppp) connection where the remote address is ppp _address

Route command is route cmd type addy netmask mask gw gway dev dn


Network configurations files

For each networl interface, there is an ifcfg file in /etc/sysconfig/network-scripts

The netconfig Utillty - a simpler tool that can used to configure a network is the netconfig utility is ia a text- based tool that allows you to input ip address subnet mask. Default gateway and primary name server . while it is much quicker than linuxconfig, it is also much less flexble.

[redwudz]

We have a Linux forum, you will likely get better answers there. Moving you.

[mikayd]

If linuxis chosen from lilo, it will will boot the kernel, Which is a vmlinuz File ( plus a Verson Number) located in the /boot Directory.

Task completd by the kernel .

Displays the linux version
Change the processor into protected mode so it can use memory aboce 1 MB
Detect how much memory you have
Set up the virtual memory subsystems


MIPS = Stands for a millon instructions per second

BogoMIPS is a bogus MIPS. Which is how many times the computer can do absolutely in 1 secound

The init Program is the first non kernel process. The init program goes throught a complicated startup sequence. Init Reads its configure file, /etc inittab and determines the run level where it should start Loacated in the /etc

A Run level is an indetifer that specifiles the current system stae such as single-user mode, Multiuser mode, Mulitiuser mode with network modes, and others.

0 Halt Halt
1 Single-user mode Single-user mode
2 Multiuser mode, Without Nfs
3 Full Multiuser mode
4. Used
5. Full Multiuser mode (with an X-based login Screen
6 Reboot


The Initab File The /etc/initab file contains the locations of all the cricps or programs that need to be run and the process to kill or terminate to complete the change. There are scripts for each of the run levels

Daemon is a background process or service that moniters and performs many crtical system functions and services.

Crond – Automatic task scheduler. Manages the execution of tasks that are executed at regular but infrequent intervals, such as rotating log files and cleaning up/tmp directories
Httpd – Daemon for apache Web server
Klogd the daemon that intercptes and displays/logs the kernel messages
Lpd – Printing daemon
Sq1uid - An http prozy with caching

Damon name then start or stop Sometimes daemon will require the full path.

Chkconfig – list commad youll see see a list of system services and whether they are stared (on) or stopped (off) in run levels 0-6.

The Lilo configuration file (/etc/lilo.conf) is a simple text file used to figure out what operating systems are installed on your system and where their boot information is located.

A Monolithic kernel is a vervy large and complex component.

Microkernals on the other hand, have a much simpler and lighter structure, as they generally just manage memory and process and provide means of interprocess commauincation.

Password is to ensure that those people who attempt to acess computer who are who they say they are

Encrytion is the process of disguising a message or data in what appears to be meaningless data ( ciper text ) to hide and protect the sensitive data form unauthorized acess.

Decryption is the process of conveying data from encrypted format to its original format

Cryptography is an art of proteching information by transforming it ( Encrypting it) into cipher text.

Key –is a string of bits used to map text into a code and to map a code back to text .

Basic form of encryption is private-key encryption.

Etc /Passwd = user accounts

If the password entry is an x. it means that shadow passwords are in use and that the user’s password is stored in /etc/shadow

Shadow passwords - take the encrypted password entries that were removed from the password and place them in a separate file called shadow. This way, the Reggular password file would be readable only by all users on the system

Root account - is like the super user top dog cram della lamma

Useradd - usseradd jsmith –d /home2/jsmith

Modifying Accounts chage the chage command allows you to modify account setting relating to account expriatin.

Delete users – userdel -r jsmith

Password - Passwd

Default Settings for users - /etc/default/useradd

Adding groups – Groupadd

Linux File systems Secound Extended File systems (Ext2)

Inode – is an index into the array of inodes held in the inode table of the of the block groups – every thing about the file

Inode bitmap – The block number of the inode allocation bitmap for this block group. This is used during inode allocation and deallocation.

Inode table – the block number of thestarting block for the inode table for this block group

The Super block Contains Descriton of the basic size and shape of the file system.

Journaling file systems are superior to static file systems when it comes to guaranteeing data integrity and increasing overall systems.

Formating an Harddrive for linux use fdisk then use the command mkfs

To see how much space and stuff use the commad fsck

Mount and unmount unmounting partition = umonut

Backup –is an extra copy of data and /or /programs.

Full back - up back ups the whole entrie drive

Incremental Backup – backs up only new files and changed files

Differential Backup – backs up new files and change files since the last back up

Cpio- is short for copy in and out


File Security

User name ( uid) A user is associated with each file on the computer. This is frequently referred to as the file owner.

Group ( or GID)- Every file is associated with a particular Gid, Which links the file to a group. This is sometimes referred to as the group owner.

Permission string Along With the user And gropu names the permission string is what Determines if you may acess a file.

Read - R - 4
Write - W -2
Execute – X – 1

Chmod 644 Report.tex


974 Mail routing and the domain system
1034 Domain Names – Concepts and Facilities
1035 Domain Names – Impemetation and Specificaton
1123 Requirements for internet Hosts – Application and Support
1886 Dns Extensions to support IP Version ^
1912 Common DNS Operation and Configuration Errors
1995 Incremental Zone Transfer in DNs
1996 A Mechanism for promt DNS Notfications of Aone Changes
2136 Dynamice Updates in the domain Name system ( DNS UPDATE )
2181 Clarifications to the DNS Specifcation
2182 Selection and operation of secondary DNs
2219 Use of DNS Aliases For Network Services
2308 Negative Caching of Dns Queies ( Dns Ncache




What linux calls the kernel – vmlinuz

The 2 boot loaders, Grub and Lilo.

Minor is a single device Major is Group of deices

Determine the device class and the Specfic device
Make Dep
Make Clean
Make Bzimage
Make Modules
In your /boot

Cp /user/src/limuxversion/system.map /boot/system.map-2.4.7-12

The cron Daemon and program allows any user in the system to schedule a program to run on any date at any time.

Cron (- u user) (-I | -r } File

/Etc

/proc and /dev directories InFormation about the kernal

It stores and and exracts files from an archive file known as a tarfile you can use a tar file on a tape drive

Dns Tranlates Domain name system freshonfreshto an ip address

Dhcp – dynamic host configration protocol it configure a host during start up an ipadress

Umask deafault mast to be used for applied to permission 0777
In the login .defs file options

Nfs a way linux shares file across the network and applicatiions

[CrayonEater]

Actually I prefer rpm -Uvh xxxxx.rpm for my installs.

And a generally easy compile will go:

./configure <any options to be enabled>
make
make install

or even ./configure <any options to be enabled> && make && make install

[Steve Stepoway]

Actually I prefer rpm -Uvh xxxxx.rpm for my installs.

apt-get is waaay better than "bare" rpm for installs. It handles all the dependencies automatically.

And a generally easy compile will go:

./configure <any options to be enabled>
make
make install

or even ./configure <any options to be enabled> && make && make install

A warning: you should never ever do a ./configure and make as root. Always chown the source files to some other user id, and do those 2 steps as that user. make install you have to do as root, but do as little as possible while root.

Steve

[mikayd]

Its Cool To see Some linux Fans here