Khirod Patra's collection

Tips on Virtual Box

2010-11-12T06:56:00.000-08:00

If you are using any Virtual box , then you mustt add your user name to the vboxgusers group, So that you get access to the USB system in Windows XP i.e.

usermod -A vboxusers

Install Oracle 10g XE on ubuntu

2010-07-18T09:16:00.000-07:00

1) download oracle oracle-xe-universal_10.2.0.1-1.0_i386.deb from the oracle official website

Then

sudo dpkg -i oracle-xe-universal_10.2.0.1-1.0_i386.deb

2) sudo /etc/init.d/oracle-xe configure

It will ask the value for some option like

Specify the HTTP port that will be used for Oracle Application Express [8080]:7070

By default the port number is 8080, be care full make sure the same port is not used by any other process, In my case tomcat is already on 8080 so i changed to 7070.

Similarly :
Specify a port that will be used for the database listener [1521]:1521

Then Specify the Password and confirm password and restart the datatabase like

Specify a password to be used for database accounts. Note that the same
password will be used for SYS and SYSTEM. Oracle recommends the use of
different passwords for each database account. This can be done after
initial configuration:
Confirm the password:

Do you want Oracle Database 10g Express Edition to be started on boot (y/n) [y]:y

It Will restart the oracle and now oracle ready to use

You can try it from SQL command line or from http://127.0.0.1:7070/apex

In the above link change the port number accordingly ,what ever you mentioned in the configuration file

from the command line of SQL, give the command

connect system/manager i.e

Note: The default database name of 10g is xe.

Size of a Symbolic Link In UNIX

2010-07-06T14:02:00.000-07:00

Check the Below Example:

lrwxrwxrwx 1 root root 8 Dec 8 2008 swbt -> /nas/usr
lrwxrwxrwx 1 root root 10 Dec 5 2008 tmp -> ../var/tmp

In the above llinks the sizes are 8 and 10 respectively . The Symbolic calculate the size according to the
number of the charaters in the link Path i.e

/nas/usr has 8 characters So the Size is 8

../var/tmp has 10 character So the Size is 10

Installing Sun Java On Ubuntu/Debian

2010-06-15T13:07:00.000-07:00

Installing Sun Java On Ubuntu/Debian

Download latest Java JDK from http://java.sun.com/j2se/1.5.0/download.jsp

(being sure not to download the .rpm, but rather the .bin)

install java-package with apt-get

(that includes binutils, fakeroot)

(Note also that java-package is in “multiverse”, so your repository list /etc/apt/sources.list needs to have that enabled)

make debian java package:

Disregarding the errors, in a tmp dir where we have copied the downloaded jdk, we do (without using sudo):

fakeroot make-jpkg jdk-1_5_0_05-linux-i586.binwhich, after ok’ing the license and extracting stuff, and trundling,after a while creates sun-j2sdk1.5_1.5.0+update06_i386.deb

then we install our newly made package, this time with sudo:

sudo dpkg -i sun-j2sdk1.5_1.5.0+update06_i386.deb“Once you’ve installed it, you’ll be up and running with the latest jdk: your JAVA_HOME is now, for example, /usr/lib/j2sdk1.5-sun. Get a command line, and enter java -version: you should see something like:

Now you have java :)

How To Restore Grub In Ubuntu

2010-05-07T11:03:00.003-07:00

Boot up your live CD

In the desktop, open terminal (Applications -> Accessories -> Terminal).

sudo grub

This will set it to grub mode

find /boot/grub/stage1

This will locate your boot partition. If you already know the location, you can ignore this step.

root (hd0,0)

Replace the (hd0,0) by your boot partition number. If your Ubuntu is installed in the second partition, then change it to (hd0,1)

setup (hd0)
quit

Reboot your system. You should be able to access the Grub bootloader now.

Find the MAC address Remotely

2010-05-06T10:49:00.000-07:00

If you can ping this host over the LAN/WAN, his MAC address will be cached in ARP table of your NIC for a while, so, from command prompt:

ping 1.2.3.4

after some echo replies from host 1.2.3.4

arp -a

and you will see MAC address of 1.2.3.4

You can try to specific as

/sbin/arp -a 192.168.1.1

You can also Try : PSTOOLS (freeware from Sysinternals) PSEXEC

Performance Refactoring to Reduce Garbage Creation(Advantage in tomcat 5)

2010-04-27T06:08:00.001-07:00

The first enhancement to look at is Tomcat 5.0's memory-profiling tools. Tomcat 5 has been carefully optimized so that it produces less object garbage for the Java VM's garbage collector to have to clean up.

A typical problem with busy Java servers is that the server software constantly instantiates new objects, and when they're not needed anymore (typically, when a request ends), the objects are not reused but instead thrown out as garbage. The garbage collector must then find and reap all such objects to reclaim the memory they occupy. This takes time and CPU cycles to do, and in the meantime the whole JVM may be paused so that the garbage collector can finish its work. This means the requests currently in process must simply wait until the garbage collector is done, which makes the whole server slow down a little. Usually, this isn't a big problem because the garbage collector is pretty efficient at collecting garbage objects. But in some cases there is so much garbage being produced that it can't keep up, and eventually the amount of free memory gets low because there is a backlog of garbage objects using lots of memory. Or sometimes a web app creates very large objects that take the garbage collector longer to finalize and destroy, so the amount of free memory is lost in large chunks but isn't being replenished quite as fast.

Tomcat 5.0 has had many garbage creation (read performance enhancement) changes since Tomcat 4.1. Tomcat 5.0's single most important garbage-creation refactoring was the new request URI mapper. After some optimization profiling, Tomcat 4.1's request pipeline was found to create excess garbage while mapping a Connector's requests to the proper Container. For Tomcat 5, a whole new mapper was implemented that generates little or no garbage (lots of object recycling is going on in there), and thus Tomcat 5.0's request pipeline performs noticeably better than that of Tomcat 4.1. This also lowers the overall memory usage compared to Tomcat 4.1, which helps to prevent OutOfMemoryExceptions in the web apps it runs, and helps Tomcat 5 to scale higher vertically (i.e. higher scalability on a single machine).

Restore The UBUNTU Panels

2010-04-15T16:16:00.000-07:00

Run These Below Commands

gconftool-2 --shutdown
gconftool --recursive-unset /apps/panel
rm -rf ~/.gconf/apps/panel
pkill gnome-panel

Connection To Oracle Through Shell Script

2010-04-13T10:04:00.000-07:00

Oracle environment variables; if not all then set at least the last two of the following:

export ORACLE_BASE=/path/to/oracle
export ORACLE_HOME=$ORACLE_BASE/product/11g
export ORACLE_TERM=xsun
export NLS_LANG=American_America.US7ASCII
export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$LD_LIBRARY_PATH
export ORACLE_PATH=$ORACLE_HOME/bin
export PATH=$ORACLE_HOME/bin:$PATH
Set the Path of Oracle SID

export ORACLE_SID=orcl (Optional).For More Information(http://www.orafaq.com/wiki/ORACLE_SID)

However, if you have a Service Name instead and your oracle instance runs off of a different port than the default, then use the following format for connecting.

sqlplus -s LOGIN/PASSSWD@SERVERNAME:ORA_PORT/SERVICE_NAME

sqlplus -s LOGIN/PASSSWD (With out Service Name and with default port)

Ex:--

#!/bin/sh -e

export ORACLE_BASE=/path/to/oracle
export ORACLE_HOME=$ORACLE_BASE/product/11g
export ORACLE_TERM=xsun
export NLS_LANG=American_America.US7ASCII
export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$LD_LIBRARY_PATH
export ORACLE_PATH=$ORACLE_HOME/bin
export PATH=$ORACLE_HOME/bin:$PATH

sqlplus -s LOGIN/PASSSWD@SERVERNAME:ORA_PORT/SERVICE_NAME << EOF > sqloutput

set pagesize 0;
select * from blah;
update blah;
commit;
exit;

How to set-up or install ZTE MG880 USB Modem in Ubuntu Jaunty 9.04

2010-01-24T11:31:00.000-08:00

1. Plug your modem into usb port.

2. To make sure if your modem has been detected by your ubuntu, use this command in your terminal.

standy@ubuntu:~$ lsusb

Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Bus 001 Device 004: ID 04f2:b098 Chicony Electronics Co., Ltd

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Bus 003 Device 003: ID 19d2:fff5

Bus 003 Device 002: ID 1bcf:0007 Sunplus Innovation Technology Inc.

Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

In here, you can see your modem vendor id and product id. 19d2:fff5 is your modem ID as CDROM storage, not as MODEM. ZTE modem has 2 function, as storage (include Windows Driver) or as modem itself. To use this modem, we must change its mode to the Modem mode with use USB_ModeSwitch – Activating Switchable USB Devices on Linux.

3. After that, we must download that software from here : http://www.draisberghof.de/usb_modeswitch/usb_modeswitch-1.0.7.tar.bz2

After you have that file, you must extract its content by using extraction software (right click that file => extract here). The content of that file is included these files :

80-usb_modeswitch.rules

README

usb_modeswitch.d

COPYING

usb_modeswitch

usb_modeswitch.h

Makefile

usb_modeswitch.c

usb_modeswitch.sh

Makefile.integrated

usb_modeswitch.conf

usb_modeswitch.tcl

by using Nautilus (type “sudo nautilus” in terminal), you must copy these files (red color files only) into :

usb_modeswitch => /usr/sbin

usb_modeswitch.conf => /etc

4. Next you must set or edit usb_modeswitch.conf with gedit.

You must search words line contain like this :

########################################################

# ZTE AC8710

# ZTE AC2726

# and others

# Many new ZTE devices use this sequence. There are

# several ID combinations; check your default

# Contributor: Michael Khurtsiya, Amit Pundir and others

DefaultVendor= 0×19d2

DefaultProduct= 0xfff5

TargetVendor= 0×19d2

TargetProduct= 0xfffe

# No. 2

;DefaultVendor= 0×19d2

;DefaultProduct= 0xfff6

;TargetVendor= 0×19d2

;TargetProduct= 0xfff1

# No. 3

;DefaultVendor= 0×19d2

;DefaultProduct= 0xfff5

;TargetVendor= 0×19d2

;TargetProduct= 0xfff1

# only for reference and 0.x versions

# MessageEndpoint=0×05

MessageContent=”5553424312345678c00000008000069f030000000000000000000000000000″

———————————————————————

You must set yours to be like that. The difference only in red words line, with delete ; symbol.

Save and exit from gedit.

5. Now on terminal you can type :

standy@ubuntu:~$ sudo usb_modeswitch

Looking for target devices …

No devices in target mode or class found

Looking for default devices …

Found default devices (1)

Accessing device 003 on bus 003 …

Using endpoints 0×05 (out) and 0×82 (in)

Inquiring device details; driver will be detached …

Looking for active driver …

No driver found. Either detached before or never attached

SCSI inquiry data (for identification)

————————-

Vendor String: ZTE

Model String: USB Storage FFFE

Revision String: 2.31

————————-

USB description data (for identification)

————————-

Manufacturer: ZTE, Incorporated

Product: USB Storage

Serial No.: 000000000002

————————-

Setting up communication with interface 0 …

Trying to send the message to endpoint 0×05 …

OK, message successfully sent

Device is gone, skipping any further commands

-> Run lsusb to note any changes. Bye.

standy@ubuntu:~$ lsusb

Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Bus 001 Device 004: ID 04f2:b098 Chicony Electronics Co., Ltd

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

Bus 003 Device 004: ID 19d2:fffe

Bus 003 Device 002: ID 1bcf:0007 Sunplus Innovation Technology Inc.

Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

6. Oke … your modem is a modem now … or in modem mode … In here, you can see your modem vendor id and product id. 19d2:fffe is your modem ID as MODEM.

Next, you must modprobe your modem as usbserial into kernel … (different method with other ubuntu version) with “sudo gedit /boot/grub/menu.lst” in terminal.

Compare, add and edit yours to be like this :

## ## End Default Options ##

title Ubuntu 9.04, kernel 2.6.28-11-generic with usbserial

root ()/ubuntu/disks

kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=EA9CAC679CAC304D loop=/ubuntu/disks/root.disk ro quiet splash

usbserial.vendor=0×19d2 usbserial.product=0xfffe

initrd /boot/initrd.img-2.6.28-11-generic

title Ubuntu 9.04, kernel 2.6.28-11-generic (recovery mode)

root ()/ubuntu/disks

kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=EA9CAC679CAC304D loop=/ubuntu/disks/root.disk ro single

initrd /boot/initrd.img-2.6.28-11-generic

title Ubuntu 9.04, memtest86+

root ()/ubuntu/disks

kernel /boot/memtest86+.bin

———————————————————————

Then instal wvdia

---------------------------------------

sudo apt-get install wvdial

then edit /etc/wvdial.conf file like

Init1 = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Modem Type = Analog Modem
Phone = #777
Username =
Password =
ISDN = 0
SetVolume = 0
FlowControl = Hardware (CRTSCTS)
Modem = /dev/ttyUSB0
Dial Command = ATDT
Baud = 460800
Stupid Mode = 1

//If you are going to use wvdial the follow the pppconfig

Close all terminal. Open new terminal and type

sudo pppconfig
in the new (below) window select Create and give ok…
Type provider name (say reliance) and give ok
Select Dynamic and give ok
Select PAP and give ok
Enter your Reliance Number and give ok
Password is same as your Reliance Number, enter it and give ok
Do not change Modem Speed
Select Tone and give ok
Enter #777 and give ok
Enter yes
Select Manual and give ok
Give your modem port. In my (most of the) case it is /dev/ttyUSB0
Now all set. Ensure Everything is fine. Select Finished then ok
Finally in the last wind select Quit and give ok
Now you have configured your modem successfully and all set to connect.
To establish internet connection type the following command in terminal…
sudo pon reliance
Ensuring connection is established use this command…
ifconfig
Now you should see entry like this…
ppp0 Link encap:Point-to-Point Protocol
inet addr:123.239.41.80 P-t-P:220.224.134.12 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:3429 errors:23 dropped:0 overruns:0 frame:0
TX packets:3683 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:2309338 (2.3 MB) TX bytes:731534 (731.5 KB)
Once the connection is established you can close the terminal.
To disconnect…
sudo poff reliance

Save and restart now …

Enable and Disable Ubuntu Root Password

2009-11-12T11:55:00.000-08:00

TO Enable root Password The Comand is

$sudo passwd root

This will prompt for a new root password and once you confirm it, you can start using the root account to login

To Disable root Password

$sudo passwd -l root

How to Install PostgreSQL Using the Source Code

2009-11-12T09:01:00.000-08:00

1. Obtain the source code from PostgreSQL website [1].
2. Unpack the source code package. Use the following bash/console command:

gunzip postgresql-8.3.3.tar.gz
tar xf postgresql-8.3.3.tar

* postgresql-8.3.3 is the name of the current version. Future versions might differ in the 8.3.3 part.
* A directory named postgresql-8.3.3 will be created under the current directory (the one you executed the above script from).
3. Change the current directory to the newly created one (postgresql-8.3.3)
4. Configure the source tree for your system and choose the installation options you want:
* Default Configuration: run the command
./configure
on your bash/console
* Custom Configuration (this is for advanced users only): you can set a lot of custom configuration options using command line options listed in the PostgreSql documentation [2]
5. Start the build process by executing the command line
gmake
in your console/bash. This might take a few minutes depending on your hardware. The last line displayed should be:
All of PostgreSQL is successfully made. Ready to install.
6. Install PostgreSql files by executing the bash/console command:
gmake install
which will install the files to /usr/local/pgsql unless you used the --prefix=PREFIX command line option, in which case the files will be installed to the path specified by PREFIX
7. Create a super-user account for PostgreSQL by executing the following command in the bash console:
adduser postgres
8. Create a directory to hold PostgreSQL data tree by executing the following commands in the bash console:
mkdir /p01/pgsql/data
chown postgres /p01/pgsql/data
9. Create PostgreSQL cluster by executing:
su - postgres
/usr/local/pgsql/bin/initdb -D /p01/pgsql/data
10. Start up the PostgreSQL server (postmaster process) by executing:
/usr/local/pgsql/bin/postmaster -D /p01/pgsql/data >logfile 2>&1 &
11. Create a PostgreSQL database in the cluster by executing:
/usr/local/pgsql/bin/createdb test
12. Log-in to the database using the psql command:
/usr/local/pgsql/bin/psql test

Install PostgreSQL on Ubuntu

2009-11-12T07:24:00.000-08:00

$ sudo apt-get install postgresql postgresql-client postgresql-contrib

$ sudo apt-get install pgadmin3

This installs the database server/client, some extra utility scripts and the pgAdmin GUI application for working with the database.

Now we need to reset the password for the ‘postgres’ admin account for the server, so we can use this for all of the system administration tasks. Type the following at the command-line (substitute in the password you want to use for your administrator account):

$ sudo su postgres -c psql template1
template1=# ALTER USER postgres WITH PASSWORD 'password';
template1=# \q

That alters the password for within the database, now we need to do the same for the unix user ‘postgres’:

$ sudo passwd -d postgres
$ sudo su postgres -c passwd

Now enter the same password that you used previously.
Then, from here on in we can use both pgAdmin and command-line access (as the postgres user) to run the database server. But before you jump into pgAdmin we should set-up the PostgreSQL admin pack that enables better logging and monitoring within pgAdmin. Run the following at the command-line:

$ sudo su postgres -c psql < /usr/share/postgresql/8.3/contrib/adminpack.sql

Finally, we need to open up the server so that we can access and use it remotely - unless you only want to access the database on the local machine. To do this, first, we need to edit the postgresql.conf file:

$ sudo gedit /etc/postgresql/8.3/main/postgresql.conf

Now, to edit a couple of lines in the ‘Connections and Authentication’ section…
Change the line:

#listen_addresses = 'localhost'

listen_addresses = '*'

and also change the line:

#password_encryption = on

password_encryption = on

Then save the file and close gedit.
Now for the final step, we must define who can access the server. This is all done using the pg_hba.conf file.¹

$ sudo gedit /etc/postgresql/8.3/main/pg_hba.conf

Comment out, or delete the current contents of the file, then add this text to the bottom of the file:

# DO NOT DISABLE!
# If you change this first entry you will need to make sure that the
# database
# super user can access the database using some other method.
# Noninteractive
# access to all databases is required during automatic maintenance
# (autovacuum, daily cronjob, replication, and similar tasks).
#
# Database administrative login by UNIX sockets
local   all         postgres                          ident sameuser
# TYPE  DATABASE    USER        CIDR-ADDRESS          METHOD

# "local" is for Unix domain socket connections only
local   all         all                               md5
# IPv4 local connections:
host    all         all         127.0.0.1/32          md5
# IPv6 local connections:
host    all         all         ::1/128               md5

# Connections for all PCs on the subnet
#
# TYPE DATABASE USER IP-ADDRESS IP-MASK METHOD
host    all         all         [ip address]          [subnet mask]  md5

and in the last line, add in your subnet mask (i.e. 255.255.255.0) and the IP address of the machine that you would like to access your server (i.e. 150.150.0.45). However, if you would like to enable access to a range of IP addresses, just substitute the last number for a zero and all machines within that range will be allowed access (i.e. 150.150.0.0 would allow all machines with an IP address 150.150.0.x to use the database server).
That’s it, now all you have to do is restart the server:

$ sudo /etc/init.d/postgresql-8.3 restart

IMPORTANT

To Work from Command line

edit this line in /etc/postgresql/8.3/main/pg_hba.conf

# Database administrative login by UNIX sockets
local   all         postgres                          ident sameuser

change ident sameuser to md5
restart your postgresql
then try login to postgreql with psql -U ‘your username’ -W then input your password

make deb file from source code in ubuntu / debian Linux with Checkinstall

2009-11-12T06:29:00.000-08:00

First You have to install checkinstall

$ sudo apt-get install checkinstall ( Or Install from synaptic Package manager)

Download the source file, such as example.tar.gz and extract it.

$ wget http://www.example.com/downloads/example.tar.gz
( Or use any common method you have used for download a file)

Now Extract the tar.gz file (it will automatically create a folder with first part of filename)
(for getting # prompt type sudo su and give your password)
#tar -xzvf example.tar.gz
#cd example

#./configure
#make
#sudo checkinstall

Now it creates a deb file and the package will install automatically.

Building .deb package from source

2009-11-12T05:47:00.000-08:00

Here's how to easily build a .deb package for ubuntu (or debian). You could build a .deb package using checkinstall, but that wouldn't include all the debian/ubuntu specifics you need. I used the following to build the ubuntu package for my next release of News notification.

First off, let's install the necessary tools:
# apt-get install autotools-dev fakeroot dh-make build-essential

Then copy your source tree into a directory in /tmp:

# cp -r news-notification-0.3 /tmp
# cd /tmp/news-notification-0.3

Now let's make the debian control files:
# dh_make
and pick Single for single binary, or whatever is appropriate for your project.

Edit the debian/control file and at least change the Maintainer and Description fields. There are a few other files you will probably want to edit.

Then run the following: (this has to be done as root)
# dpkg-buildpackage -rfakeroot