RedHat relies new updates Red Hat Enterprise Linux 5.4 Server of Red Hat Enterprise Linux 5
with some changes and with new driver database
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Showing newest posts with label Linux. Show older posts
Showing newest posts with label Linux. Show older posts
Redhat recently introduce the RHEL 5.3 with the new enhance capability, like improve vitalization encrypted file system and much more improvement
Read full story from hear
http://www.redhat.com/about/news/prarchive/2009/rhel_5_3.html/?intcmp=70160000000Hh4WAAS
BackTrack is the very famous Live CD Linux Distribution, and it is use for Penetration testing and it has wide range of security tools, to connect BackTrack computer with the network you have to configure IP address on the LAN Interface
To configure IP Address on the eth0 interface
#ifconfig eth0 10.0.12.13
If you want to configure IP Address with Subnetmask use following COmmand
#ifconfig eth0 10.0.12.50 netmask 255.255.248.0
To manually configure default gateway:
#route add default gw 10.0.8.1 eth0
To Configure DNS servers IP Address:
#echo nameserver 4.2.2.1 > /etc/resolv.conf
#echo nameserver 4.2.2.2 >> /etc/resolv.conf
Turn on the LAN Card
#ifconfig eth0 up
To see Full Information about LAN Card
#ifconfig -a
This is very obvious question about dual booting computer, means if you have install Windows and Linux both in deferent partitions, and any reason you want to uninstall Linux from your computer, to do this some users delete the Linux partition but groub is still in MBR and after deleting Linux partition they will face new problem when computer will reboot the system load groub from MBR but groub configuration file also deleted with Linux partitions and now groub prompt will appear and your system will not boot Linux as well as Windows also, to solve this problem you have to remove groub from MBR
With the following step by step procedure you can uninstall or delete Linux completely and safely.
Requirements:
You need a windows 98 startup disk or windows installation bootable CD.
Step by step procedure:
1. First Reboot your computer with windows 98 start up disc or Windows CD (with Recovery Console option) and type the following command.
“fixmbr”
2. "fixmbr" command will replace grub loader of Linux and repair yours bootloader and rewrite ntldr on MBR of Hard Disk, now you will see only Windows in the boot menu.
3. Now Boot up with your windows operation system
4. And with use of Disk Manager delete the Linux partition
To run Disk Manager
Go to Start > Control Panel > Administrative Tools > Computer Management
5. Go to Disk Management under “Storage”
6. Select your Hard Disk and then select the Linux partition and delete the Linux partition this will delete Linux and grub from boot partition of Linux.
Next time you will boot your computer Windows automatically boot and no groub menu will appear on your boot screen
If you have any problem in the procedure given above leave a comment here…
"root" is the super user of Linux Operating System and he has full privilege to do anything on it. and if you forgot the root users password then it is very helpless situation for you. in this situation you will not able to do any changes in Linux Operating system, and as a standard user you do not have such privilege who has root user. but do not vary about this problem, Linux operating system has solution for this problem.
Before do this you need some basic concept about "init" process. init is father of all Linux processes and it is first process which is executed at the time of booting after the loading Linux kernel in to the RAM. By default init has 7 run levels and every run level has specific use.
Default runlevel. The runlevels used by Linux are:
# 0 - halt (Do NOT set initdefault to this)
# 1 - Single user mode
# 2 - Multiuser, without NFS (The same as 3, if you do not have networking)
# 3 - Full multiuser mode
# 4 - unused
# 5 - X11
# 6 - reboot (Do NOT set initdefault to this)
This run levels you can change by 3 different ways in Linux Operating System
- In first method you can change run level from init configuration (/etc/inittab) file it will be permanent,
- In Second method run levels can change from Linux command prompt,
- You can also change run level temporary at the booting time.
For recover root password you will use third method change run level while booting. Step by step procedure describe below
Step - 1. Boot you which root Linux and grub boot loader screen will appear press "Enter" key and you will be in following screen, and hear type "e" to go in to edit mode.
Step - 2. In the edit windows select line which start from "kernel" and again press "e" to edit this line.
Step - 3. Now you are in Line editing mode and curser will be at end of the kernel line, at the end of line first press "space bar" and then type "1" and press "Enter" and then press "b" to boot the Linux with the new setting. and boot will start.
Step - 4. Wow see what happed you are in shall prompt without username and password, this is magic of Single user mode in Single user mode Linux never ask for username password to enter in to Linux system.
Step -5. Now at shall prompt type "passwd" command to change root password and for change password system will not ask for previous password, hear type new password and retype same password and you root password is changed reboot you Linux and login as a root with the new password and enjoy it.
Warning - In our world every thing has good side as well as bad side also. Linux Signal user mode also has bad side if anybody has physical accesses on you system so he can use single user mode to change root password, so you need to secure you systems single user mode for this two sequence of methods
- Protect your system with Bios Password.
- And use grub password to protect the grub editing mode while booting
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Shutdown is common process on every Computer. After completing the work most of the us shutdown the computer, shutdown process completed in sequence of task by computer and Operating System. In shutdown process Operating System will end every running process step by step and save unsaved information before power goes off.
If you are near the computer then you can shutdown it properly. But it is not a easy task to shutdown computer from remote and make sure all the running process ends before power turn off.
To doing this you can schedule shutdown process on particular time for example Like shutdown at you Sleeping time, Time to go home after office hours, etc. Every Operating has its on mechanism for task scheduling. through which you can define task for auto shutdown.
Bellow is a step by step procedure on How to schedule shutdown process in Windows and Linux
1. Schedule Shutdown in Linux
2. Schedule Shutdown in Windows
Some time we need shutdown process be automatically and our computer Shutdown automatically on particular time, this can be possible with Job scheduling
In Linux For Job Scheduling 2 utility available one is "at" and second is "cron"
at- Execute a task at a specific time. and "at" is Useful only to schedule one job at a time or a single future event. in this we can not define recurring events or daily events.
for shutting down Linux automatically at 11:59 pm, use following example.
# at 11:59pm |
Some more command for "at"
- atq - List the current "at" jobs pending.
- atrm - Used to remove pending "at" jobs.
Linux Cron job to Shutdown Linux server/Desktop system:
cron – cron is Linux command line task scheduler, Useful to schedule recurring events or daily events such as backup, check system security etc.
Step 1 - Login as root user and at shell prompt type crontab -e command so that you can add cronjob.
| # crontab -e |
Step 2 - above command open root users crontab file in vim editor and then Append following entry to it (shutdown at 23:59 hrs (24 hrs format).59 23 * * * /sbin/shutdown -h now
(3) Save the changes and exit from vim editor to shell prompt.
Oracle Database administration is a very hot profession of today and if you know how to install Oracle database on Linux then you become a very valuable person. Both technology is in demand, and together oracle & Linux create a very secure & sophisticated environment.
Installing Oracle on Linux is little bit tough job. In this article I am discussing procedure to install Oracle on Linux. With the help of this article installation will be like playing the game. good luck.
If you face any problem during or after the installation please post your comment. I will try my best to answer your question and resolve problem.
Installing Oracle Database On Linux – A Step by step Guide
Hardware Requirement for Oracle Installation on RedHat Linux
Processor - Minimum Bettor to you have P4 and equivalent of P4 or later version of processor
RAM - The minimum RAM required for oracle installation is 1024MB , for know the RAM on PC
# grep MemTotal /proc/meminfo
MemTotal: 1034680 kB
HDD Space - 2.5GB of available disk space for the Oracle Database software and another 1.2GB for the database. The /tmp directory needs at least 400MB of free space. To check the available disk space on your system, run the following command:
# df -h
Swap - In Linux Swap space should be twice the amount of RAM if your system have 1 GB of RAM then you should have 2 GB of Swap Space, to know the Swap space use following command
# grep SwapTotal /proc/meminfo
SwapTotal: 1534196 kB
Software Requirement for Oracle Installation on RedHat Linux
RedHat Enterprise Linux 5 or RedHat Enterprise Linux 4
Kernel Version Should not be bellow then 2.6
to know kernel version use following command
# uname -r
2.6.9-22.EL
Now, Verify following packages and its Version which is required for Oracle Database, installed or not
Required package versions (or later):
binutils-2.15.92.0.2-10.EL4
compat-db-4.1.25-9
control-center-2.8.0-12
gcc-3.4.3-9.EL4
gcc-c++-3.4.3-9.EL4
glibc-2.3.4-2
glibc-common-2.3.4-2
gnome-libs-1.4.1.2.90-44.1
libstdc++-3.4.3-9.EL4
libstdc++-devel-3.4.3-9.EL4
make-3.80-5
pdksh-5.2.14-30
sysstat-5.0.5-1
xscreensaver-4.18-5.rhel4.2
libaio-0.3.96
openmotif21-2.1.30-11.RHEL4.2
for verifying abow package in your installed Linux Openrating system You can use this single line command to verify packages and its version
# rpm -q binutils compat-db control-center gcc gcc-c++ glibc glibc-common gnome-libs libstdc++ libstdc++-devel make pdksh sysstat xscreensaver libaio openmotif21
Configuring Linux for Oracle
Before starting Oracle on Linux first we have to configure Linux Operating system with root user, fallowing configuration required on Linux before starting Oracle installing.
1. Create the Oracle Groups and User Account
create the two Linux groups name "oinstall" and "dba" and one user account with name "oracle" and this user should be member of above 2 group that will be used to install and maintain the Oracle Database software. for doing this Execute the following commands as root:
# /usr/sbin/groupadd oinstall
# /usr/sbin/groupadd dba
# /usr/sbin/useradd -m -g oinstall -G dba oracle
Then Check the GID and UID of newly created groups and user, with this
# id oracleuid=501(oracle) gid=502(oinstall) groups=502(oinstall),503(dba)
2.Set the password on the oracle account:
# passwd oracle
Changing password for user oracle.
New password:
Retype new password:
passwd: all authentication tokens updated successfully.
3.Create Directories
Now create directories and define "oracle" user as a owner and "oinstall" as a group of newly created directory and also change permission on this directory to 775, this directory will use to store the Oracle Database software and the database files..
Issue the following commands as root:
# mkdir -p /u01/app/oracle
# chown -R oracle:oinstall /u01/app/oracle
# chmod -R 775 /u01/app/oracle
4.Configuring the Linux Kernel Parameters
Oracle Database requires the kernel parameter settings shown below. The values given are minimums, so if your system uses a larger value, don't change it.
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default=262144
net.core.wmem_default=262144
net.core.rmem_max=262144
net.core.wmem_max=262144
you can set this parameters by simply open the file with the any text editor of Linux otherwise use cut command like following and just cut and paste the following commands while logged in as root.
# cat >> /etc/sysctl.conf <<EOF
> kernel.shmall = 2097152
> kernel.shmmax = 536870912
> kernel.shmmni = 4096
> kernel.sem = 250 32000 100 128
> fs.file-max = 65536
> net.ipv4.ip_local_port_range = 1024 65000
> EOF
# /sbin/sysctl -p
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
kernel.shmall = 2097152
kernel.shmmax = 536870912
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default = 262144
net.core.wmem_default = 262144
net.core.rmem_max = 262144
net.core.wmem_max = 262144
Oracle recommends setting limits on the number of processes and open files each Linux account may use. To make these changes, cut and paste the following commands as root:
cat >> /etc/security/limits.conf <<EOF
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
EOF
cat >> /etc/pam.d/login <<EOF
session required /lib/security/pam_limits.so
EOF
Note - For RHEL4, use the following for defining user settings:
cat >> /etc/profile <<EOF
if [ \$USER = "oracle" ]; then
if [ \$SHELL = "/bin/ksh" ]; then
ulimit -p 16384
ulimit -n 65536
else
ulimit -u 16384 -n 65536
fi
umask 022
fi
EOF
cat >> /etc/csh.login <<EOF
if ( \$USER == "oracle" ) then
limit maxproc 16384
limit descriptors 65536
umask 022
endif
EOF
Starting the Installation of Oracle
Use the graphical login to log in as oracle user.
Then after the login locate the installation directory and Start the Oracle Universal Installer from software location and follow the following installations steps
$ ./runInstallerafter the starting the installation process follow the these steps and Options1. Select Installation Method
- Select Basic Installation
- Oracle Home Location: /u01/app/oracle/product/10.2.0/db_1
- Installation Type: Enterprise Edition (1.3GB)
- UNIX DBA Group: oinstall
- Make sure Create Starter Database is checked
- Global Database Name: demo1
- Enter the Database Password and Confirm Password
- Click on Next
2. Specify Inventory Directory and Credentials
- Inventory Directory: /u01/app/oracle/oraInventory
- Operating System group name: oinstall
- Click on Next
3.Product-specific Prerequisite Checks
- If you've been following the steps in this guide, all the checks should pass without difficulty. If one or more checks fail, correct the problem before proceeding.
- Click on Next
4.Summary
- A summary of the products being installed is presented.
- Click on Install.
5.Configuration Assistants
- The Oracle Net, Oracle Database, and iSQL*Plus configuration assistants will run automatically
6.Execute Configuration Scripts
- At the end of the installation, a pop up window will appear indicating scripts that need to be run as root. Login as root and run the indicated scripts.
- Click on OK when finished.
7.End of Installation
- Make note of the URLs presented in the summary, and click on Exit when ready.
8.Congratulations! Your new Oracle Database database is up and ready for use.
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Turn your Old PC in Home Theater
Now a day music is a part of our life, and we are lisning music in every ware in Car, in Bus, in Train, in Airoplane, when we are walking, and in home also, but to listing good quality music in home we need good quality Music System and the cost is very high, so now we have solution we can trun our Old PC in to Home Theater in very less cost.
GeeXboX is a free embedded Linux distribution which aims at turning your computer into a so called Home Theater PC or Media Center. Being a standalone LiveCD-based distribution, it's a ready to boot operating system than works on any Pentium-class x86 computer or PowerPC Macintosh, implying no software requirement. You can even use it on a diskless computer, the whole system being loaded in RAM.
GeeXboX, with the OS supporting :
* MPEG 1/2 movies (MPG files, VCDs, DVDs ...)
* MPEG 4 movies (DivX, XviD, H.264 ...)
* RealMedia and Windows Media movies.
* OggMedia streams
* Matroska streams
* Audio streams like : MP3, Ogg/Vorbis, WAV (AudioCD), AC3, DTS, MusePack (MPC), FLAC ...
* Network streams : WebRadio and WebTV through SHOUTcast.
* Watching analog TV and digital DVB
* Playing analog Radio streams.
* Playing files from your local network (LAN) through remote NFS, Samba (i.e. Windows) or UPnP shares.
people who want to run .net on linux.
MONO is the Software
Mono provides the necessary software to develop and run .NET client and server applications on Linux, Solaris, Mac OS X, Windows, and Unix. Sponsored by Novell, the Mono open source project has an active and enthusiastic contributing community and is positioned to become the leading choice for development of Linux applications.
There are many applications available that run on Mono
MonoDevelop
MonoDevelop is a free GNOME IDE primarily designed for C# and other .NET languages.
The latest release of RedHat is Fedora 9 has a new inbuilt feature "Disk Encryption" and it introducing new file system ext4 which is still in under development but more powerful and faster the ext3 file system. With Disk Encryption feature your valuable data on fedora 9 installed computer now is very secure so you can encrypt your data on your mobile computer on your server or on your desktop
http://www.redhatmagazine.com/2007/01/18/disk-encryption-in-fedora-past-present-and-future/
RedHat launch new update (update 2 ) for RedHat Enterprise Linux 5, it has new tool and Security updates
RedHat Enterprise Linux is Server platform from RedHat which is widely use in industry for Servers, RedHat RHEL platform is highly securer and Stable Linux flavor
RedHat define 18 month life cycle for RHEL and after 18 month RedHat launch new Version of RHEL currently RHEL 5 is latest one
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