Most useful Dictionary and Views for oracle dba

Most useful Dictionary and Views for oracle dba .

Data Dictionary
Which users are in the database password file:
V$PWFILE_USERS

Where values set in the init.ora file can be viewed – all parameters:
V$PARAMETER

Script used to create the objects that comprise the data dictionary:
catalog.sql

To grant a special role to users so they can look at DBA views:
SELECT_CATALOG_ROLE

Information about all database objects in the database:
DBA_OBJECTS

Information about all tables in the database:
DBA_TABLES

Information about all indexes in the database:
DBA_INDEXES

Information about all views (including dictionary views) in the database:
DBA_VIEWS

Information about all sequences in the database:
DBA_SEQUENCES

Information about all users in the database:
DBA_USERS

Information about all constraints in the database:
DBA_CONSTRAINTS

Information about all table columns that have constraints on them:
DBA_CONS_COLUMNS

Information about all columns that have indexes on them in the database:
DBA_IND_COLUMNS

Information about all columns in all the tables in the database:
DBA_TAB_COLUMNS


Information about all the roles in the database:
DBA_ROLES

Information about all object privileges in the database:
DBA_TAB_PRIVS

Information about all system privileges granted to all users in the database:
DBA_SYS_PRIVS

Displays all PL/SQL source code in the database:
DBA_SOURCE

Information about all triggers in the database:
DBA_TRIGGERS

Information about object privileges granted to roles
ROLE_TAB_PRIVS

Information about system privileges granted to roles
ROLE_SYS_PRIVS

Information about roles granted to roles
ROLE_ROLE_PRIVS

Information about all tablespaces in the database:
DBA_TABLESPACES

Information about all profiles in the database:
DBA_PROFILES


For all parameters?
V$PARAMETER

General information about the database mounted to your instance:
V$DATABASE

Most information about the performance of the database is kept here:
V$SYSSTAT

Most information about the performance for individual user sessions is stored here:
V$SESSION , V$SESSTAT

Information about online redo logs (2)
V$LOG, V$LOGFILE

Information about datafiles
V$DATAFILE

Basic information about control files, and the two columns it has:
V$CONTROLFILE. STATUS / NAME

An object you can query to obtain a listing of all data dictionary objects (4)
CATALOG, CAT, DICTIONARY, DICT.

When the control file was created, Sequence Number, most recent SCN:
V$DATABASE

Information stored in different sections of the control file, Sequence Number:
V$CONTROLFILE_RECORD_SECTION

To see the names and locations of all control files in the db? (2)
V$PARAMETER. V$CONTROLFILE


Tablespace and Datafiles
Temporary Segments:
Name, tablespace location, and owner of temporary segments:
DBA_SEGMENTS

Size of temporary tablespaces, current number of extents allocated to sort segments, and sort segment high-water mark information. Space usage allocation for temporary segments:
V$SORT_SEGMENT

Types of sorts that are happening currently on the database
V$SORT_USAGE

To see the username corresponding with the session:
V$SESSION

Information about every datafile in the database associated with a temporary tablespace:
DBA_TEMP_FILES

Similar to DBA_TEMP_FILES, this performance view gives Information about every datafile in the database associated with a temporary tablespace:
V$TEMPFILE

Storage Structures
A summary view, contains all types of segments and their storage parameters, space utilization settings:
DBA_SEGMENTS

Tablespace quotas assigned to users:
DBA_TS_QUOTAS

Segment name, type, owner, total bytes of extent, name of tablespace storing the extent:
DBA_EXTENTS

The location and amount of free space by tablespace name:
DBA_FREE_SPACE

The location of free space in the tablespace that has been coalesced:
DBA_FREE_SPACE_COALESCED

Information about datafiles for every tablespace
DBA_DATAFILES

Performance view for information for datafiles for every tablespace
V$DATAFILE

To see the total amount of space allocated to a table?
DBA_EXTENTS

Table creation timestamp, information about the object ID:
DBA_OBJECTS

High water mark, all storage settings for a table, and statistics collected as part of the analyze (for row migration) operation on that table
DBA_TABLES

Information about every column in every table:
DBA_TAB_COLUMNS

To determine how many columns are marked unused for later removal?
DBA_UNUSED_COL_TABS

To find the number of deleted index entries ?
INDEX_STATS

To determine the columns on a table that have been indexed:
DBA_ID_COLUMNS

The dynamic view to show whether the index is being used in a meaningful way?
V$OBJECT_USAGE

To see whether a constraint exists on a particular column?
DBA_CONS_COLUMNS
To see the constraints associated with a particular table:
DBA_CONSTRAINTS

To find the username, ID number, (encrypted) password, default and temporary tablespace information, user profile of a user, password expiry date:
DBA_USERS

To all objects, which objects belong to which users, how many objects a user has created?
DBA_OBJECTS

Resource-usage parameters for a particular profile:
DBA_PROFILES

Identifies all resources in the database and their corresponding cost:
RESOURCE_COST

Identifies system resource limits for individual users:
USER_RESOURCE_LIMITS

Shows all system privileges:
DBA_SYS_PRIVS

Show all object privileges:
DBA_TAB_PRIVS

Shows all privileges in this session available to you as the current user:
SESSION_PRIVS

Views for audits currently taking place are created by this script:
cataudit.sql

a list of audit entries generated by the exists option of the audit command:
DBA_AUDIT_EXISTS

A list of audit entries generated for object audits:
DBA_AUDIT_OBJECT

A list of audit entries generated by session connects and disconnects:
DBA_AUDIT_SESSION

A list of audit entries generated by statement options of the audit command:
DBA_AUDIT_STATEMENT

A list of all entries in the AUD$ table collected by the audit command:
DBA_AUDIT_TRAIL

To determine the roles available in the database, the names of all the roles on the database and if a password is required to use each role:
DBA_ROLES

Names of all users and the roles granted to them:
DBA_ROLE_PRIVS

All the roles and the roles that are granted to them:
ROLE_ROLE_PRIVS

Which system privileges have been granted to a role:
DBA_SYS_PRIVS

All the system privileges granted only to roles:
ROLE_SYS_PRIVS

All the object privileges granted only to roles:
ROLE_TAB_PRIVS

All the roles available in the current session:
SESSION_ROLES

Which object privilege has been granted to a role:
DBA_TAB_PRIVS

To display the value of the NLS_CHARACTERSET parameter:
NLS_DATABASE_PARAMETERS







Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Transportable Tablespaces

Transportable Tablespaces

Transportable tablespaces were introduced in Oracle 8i to allow whole tablespaces to be copied between databases in the time it takes to copy the datafiles. In Oracle 8i one of the restrictions was that the block size of both databases must be the same. In Oracle 9i the introduction of multiple block sizes has removed this restriction. In this article I will run through a simple example of transporting a tablespace between two databases.

Setup
Source Database
Destination Database
Cross-Platform Tablespace Conversions
Related articles.

Oracle Data Pump in Oracle Database 10g (expdp and impdp)
Data Pump Enhancements in Oracle Database 11g Release 1
SQL Developer 3.1 Data Pump Wizards (expdp, impdp)
Cross-Platform Tablespace Conversion
Setup

For this example I'm going to create a new tablespace, user and table to work with in the source database.

CONN / AS SYSDBA

CREATE TABLESPACE test_data
DATAFILE '/u01/app/oracle/oradata/DB11G/test_data01.dbf'
SIZE 1M AUTOEXTEND ON NEXT 1M;

CREATE USER test_user IDENTIFIED BY test_user
DEFAULT TABLESPACE test_data
TEMPORARY TABLESPACE temp
QUOTA UNLIMITED ON test_data;

GRANT CREATE SESSION, CREATE TABLE TO test_user;

CONN test_user/test_user

CREATE TABLE test_tab (
id NUMBER,
description VARCHAR2(50),
CONSTRAINT test_tab_pk PRIMARY KEY (id)
);

INSERT /*+ APPEND */ INTO test_tab (id, description)
SELECT level,
'Description for ' || level
FROM dual
CONNECT BY level <= 10000; COMMIT; Source Database For a tablespace to be transportable it must be totally self contained. This can be checked using the DBMS_TTS.TRANSPORT_SET_CHECK procedure. The TS_LIST parameter accepts a comma separated list of tablespace names and the INCL_CONSTRAINTS parameter indicates if constraints should be included in the check. CONN / AS SYSDBA EXEC SYS.DBMS_TTS.TRANSPORT_SET_CHECK(ts_list => 'TEST_DATA', incl_constraints => TRUE);

PL/SQL procedure successfully completed.

SQL>
The TRANSPORT_SET_VIOLATIONS view is used to check for any violations.

SELECT * FROM transport_set_violations;

no rows selected

SQL>
Assuming no violations are produced we are ready to proceed by switching the tablespace to read only mode.

SQL> ALTER TABLESPACE test_data READ ONLY;

Tablespace altered.

SQL>
Next we export the tablespace metadata using the export (expdp or exp) utility. If you are using 10g or above you should use the expdp utility. This requires a directory object pointing to a physical directory with the necessary permissions on the database server.

CONN / AS SYSDBA
CREATE OR REPLACE DIRECTORY temp_dir AS '/tmp/';
GRANT READ, WRITE ON DIRECTORY temp_dir TO system;
We can now export the tablespace metadata.

$ expdp userid=system/password directory=temp_dir transport_tablespaces=test_data dumpfile=test_data.dmp logfile=test_data_exp.log
If you are using a version prior to 10g, you do not need the directory object and your command would look something like this.

$ exp userid='system/password as sysdba' transport_tablespace=y tablespaces=test_data file=test_data.dmp log=test_data_exp.log
Copy the datafile to the appropriate location on the destination database server. Also copy the dump file to a suitable place on the destination database server. You may use binary FTP or SCP to perform this copy.

The source tablespace can now be switched back to read/write mode.

ALTER TABLESPACE test_data READ WRITE;

Tablespace altered.

SQL>
Destination Database

Create any users in the destination database that owned objects within the tablespace being transported, assuming they do not already exist.

CONN / AS SYSDBA

CREATE USER test_user IDENTIFIED BY test_user;
GRANT CREATE SESSION, CREATE TABLE TO test_user;
Now we import the metadata into the destination database. If you are using 10g or above you should use the impdp utility. This requires a directory object pointing to a physical directory with the necessary permissions on the database server.

CONN / AS SYSDBA
CREATE OR REPLACE DIRECTORY temp_dir AS '/tmp/';
GRANT READ, WRITE ON DIRECTORY temp_dir TO system;
We can now import the tablespace metadata.

$ impdp userid=system/password directory=temp_dir dumpfile=test_data.dmp logfile=test_data_imp.log transport_datafiles='/u01/app/oracle/oradata/DB11GB/test_data01.dbf'
If you are using a version prior to 10g, you do not need the directory object and your command would look something like this.

$ imp userid='system/password as sysdba' transport_tablespace=y datafiles='/u01/app/oracle/oradata/DB11GB/test_data01.dbf' tablespaces=test_data file=test_data.dmp log=test_data_imp.log
Switch the new tablespace into read write mode.

SQL> ALTER TABLESPACE test_data READ WRITE;

Tablespace altered.

SQL>
The tablespace is now available in the destination database.

SELECT tablespace_name, plugged_in, status
FROM dba_tablespaces
WHERE tablespace_name = 'TEST_DATA';

TABLESPACE_NAME PLU STATUS
------------------------------ --- ---------
TEST_DATA YES ONLINE

1 row selected.

SQL>
Cross-Platform Tablespace Conversions

If you are transporting tablespaces between platforms you need to perform Cross-Platform Tablespace Conversions.

For more information see:

Transporting Tablespaces Between Databases
Oracle Data Pump in Oracle Database 10g (expdp and impdp)
Data Pump Enhancements in Oracle Database 11g Release 1
SQL Developer 3.1 Data Pump Wizards (expdp, impdp)
Cross-Platform Tablespace Conversion
Hope this helps. Regards Tim...
















Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

How to see the database is open (mount or unmont ) state in 11g ?

select database_status from v$instance
select * from v$database

_______________________________________________________________________________________________


2. HOW MUCH SPACE IS AVAILABLE IN UNDO N HOW MUCH IS USED


SELECT d.tablespace_name, round(((NVL(f.bytes,0) + (a.maxbytes - a.bytes))/1048576+
u.exp_space),2)
as max_free_mb, round(((a.bytes - (NVL(f.bytes,0)+ (1024*1024*u.exp_space)))*100/a.maxbytes),2)
used_pct FROM sys.dba_tablespaces d, (select tablespace_name, sum(bytes) bytes,
sum(greatest(maxbytes,bytes)) maxbytes from sys.dba_data_files group by tablespace_name) a,
(select tablespace_name, sum(bytes) bytes from sys.dba_free_space group by tablespace_name) f ,
(select tablespace_name , sum(blocks)*8/(1024) exp_space from
dba_undo_extents where status NOT IN ('ACTIVE','UNEXPIRED') group by tablespace_name) u
WHERE d.tablespace_name = a.tablespace_name(+) AND d.tablespace_name = f.tablespace_name(+)
AND d.tablespace_name=u.tablespace_name AND d.contents = 'UNDO' AND u.tablespace_name = (select
UPPER(value)
from v$parameter where name = 'undo_tablespace');

3. How much active,expired and unexpired

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



set linesize 152

col tablespace_name for a20

col status for a10

select tablespace_name,status,count(extent_id) "Extent Count",
sum(blocks) "Total Blocks",sum(bytes)/(1024*1024*1024) spaceInGB
from dba_undo_extents
group by tablespace_name, status having tablespace_name=upper('&TSNAME')
order by tablespace_name;
(2:35:42 AM) vipul.pahuja@oracle.com: SQL> select * from t11;

SALARY
----------
12000

SQL> select tablespace_name,status,count(extent_id) "Extent Count",
sum(blocks) "Total Blocks",sum(bytes)/(1024*1024*1024) spaceInGB
from dba_undo_extents
group by tablespace_name, status having tablespace_name=upper('&TSNAME')
order by tablespace_name; 2 3 4 5
Enter value for tsname: UNDOTBS1
old 4: group by tablespace_name, status having tablespace_name=upper('&TSNAME')
new 4: group by tablespace_name, status having tablespace_name=upper('UNDOTBS1')

TABLESPACE_NAME STATUS Extent Count Total Blocks SPACEINGB
------------------------------ --------- ------------ ------------ ----------
UNDOTBS1 EXPIRED 33 744 .00567627
UNDOTBS1 UNEXPIRED 16 1208 .009216309

SQL> update t11 set salary=15000 where salary=12000;

1 row updated.

SQL> select tablespace_name,status,count(extent_id) "Extent Count",
sum(blocks) "Total Blocks",sum(bytes)/(1024*1024*1024) spaceInGB
from dba_undo_extents
group by tablespace_name, status having tablespace_name=upper('&TSNAME')
order by tablespace_name; 2 3 4 5
Enter value for tsname: UNDOTBS1
old 4: group by tablespace_name, status having tablespace_name=upper('&TSNAME')
new 4: group by tablespace_name, status having tablespace_name=upper('UNDOTBS1')

TABLESPACE_NAME STATUS Extent Count Total Blocks SPACEINGB
------------------------------ --------- ------------ ------------ ----------
UNDOTBS1 ACTIVE 1 128 .000976563
UNDOTBS1 EXPIRED 33 744 .00567627
UNDOTBS1 UNEXPIRED 15 1080 .008239746

SQL> update t11 set salary=20000 where salary=15000;

1 row updated.

SQL> select tablespace_name,status,count(extent_id) "Extent Count",
sum(blocks) "Total Blocks",sum(bytes)/(1024*1024*1024) spaceInGB
from dba_undo_extents
group by tablespace_name, status having tablespace_name=upper('&TSNAME')
order by tablespace_name; 2 3 4 5
Enter value for tsname: UNDOTBS1
old 4: group by tablespace_name, status having tablespace_name=upper('&TSNAME')
new 4: group by tablespace_name, status having tablespace_name=upper('UNDOTBS1')

TABLESPACE_NAME STATUS Extent Count Total Blocks SPACEINGB
------------------------------ --------- ------------ ------------ ----------
UNDOTBS1 ACTIVE 1 128 .000976563
UNDOTBS1 EXPIRED 33 744 .00567627
UNDOTBS1 UNEXPIRED 15 1080 .008239746

SQL> update t11 set salary=25000 where salary=20000;

1 row updated.

SQL> select tablespace_name,status,count(extent_id) "Extent Count",
sum(blocks) "Total Blocks",sum(bytes)/(1024*1024*1024) spaceInGB
from dba_undo_extents
group by tablespace_name, status having tablespace_name=upper('&TSNAME')
order by tablespace_name; 2 3 4 5
Enter value for tsname: UNDOTBS1
old 4: group by tablespace_name, status having tablespace_name=upper('&TSNAME')
new 4: group by tablespace_name, status having tablespace_name=upper('UNDOTBS1')

TABLESPACE_NAME STATUS Extent Count Total Blocks SPACEINGB
------------------------------ --------- ------------ ------------ ----------
UNDOTBS1 ACTIVE 1 128 .000976563
UNDOTBS1 EXPIRED 33 744 .00567627
UNDOTBS1 UNEXPIRED 15 1080 .008239746

SQL> commit;

Commit complete.

SQL> select tablespace_name,status,count(extent_id) "Extent Count",
sum(blocks) "Total Blocks",sum(bytes)/(1024*1024*1024) spaceInGB
from dba_undo_extents
group by tablespace_name, status having tablespace_name=upper('&TSNAME')
order by tablespace_name; 2 3 4 5
Enter value for tsname: UNDOTBS1
old 4: group by tablespace_name, status having tablespace_name=upper('&TSNAME')
new 4: group by tablespace_name, status having tablespace_name=upper('UNDOTBS1')

TABLESPACE_NAME STATUS Extent Count Total Blocks SPACEINGB
------------------------------ --------- ------------ ------------ ----------
UNDOTBS1 EXPIRED 34 752 .005737305
UNDOTBS1 UNEXPIRED 15 1200 .009155273

SQL>






Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

How to unlock the user in oracle Sql

How to unlock the user in oracle 

check more videos on
http://www.youtube.com/channel

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Oracle Certification Path

 Oracle certification path

For those who are looking for oracle certification ( OCA / OCP) in 10g

Oracle Associate Certification Path ( OCA)

STEP 1  

1Z0-051 Oracle Database 11g: SQL Fundamentals I

STEP 2  

1Z0-042 Oracle Database 10g: Administration I

Than you  are  Oracle Database 10gAdministrator Certified Associate

Now Next step is  Oracle Database 10g Administrator Certified Professional

 

 

Oracle Professional Certification Path (OCP)

STEP 1 - PRIOR CERTIFICATION

Oracle Database 10g Administrator Certified Associate

STEP 2 - COMPLETE TRAINING

Complete one of the approved advanced courses

STEP 3 - PASS THIS EXAM  1Z0-043   Oracle Database 10g: Administration II

STEP 4 - COMPLETE THIS FORM

Complete the Course Submission Form

Oracle Database 10gAdministrator Certified Professional

for more info check Oracle web page .



Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Download and Installation of Oracle VM Virtual machine

Download and Installation of Oracle VM Virtual machine

       
                         Here we will see, from where we can download the oracle Vm virtual machine and how install it .also you can find   Prerequisites , Download location and   Installation process..

                               watch more on Chetan yadav videos's
  for screen shot of download and installation of oracle VM virtual machine more....
 download docs from Document

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav

Creating a Swap Partition In Linux

Creating a Swap Partition In Linux


Step 1 ) Create the required partition (say 9 partition)

[root@client1 ~]# fdisk -l

[root@client1 ~]# fdisk /dev/hda
:p
:n
:t  { to change the partition ID}
:82 { for swap partition }
:w  { save & exit }
[root@client1 ~]#
[root@client1 ~]# partprobe /dev/hda

[root@client1 ~]# fdisk –l

Step 2 ) Make the partition as swap

[root@client1 ~]# mkswap /dev/hda9

To see the status

[root@client1 ~]# swapon –s

To on the swap partition

[root@client1 ~]# swapon /dev/hda9

Again  see the status

[root@client1 ~]# swapon -s

To put Off the swap partition

[root@client1 ~]# swapoff /dev/hda9

[root@client1 ~]# swapon –s






Logical Volume Manager


To view the Hard disk name and partition information

[root@client24 ~]# fdisk -l

Disk /dev/hda: 40.0 GB, 40020664320 bytes
255 heads, 63 sectors/track, 4865 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1          13      104391   83  Linux
/dev/hda2              14         523     4096575   83  Linux
/dev/hda3             524         778     2048287+  83  Linux
/dev/hda4             779        4865    32828827+   5  Extended
/dev/hda5             779         905     1020096   83  Linux
/dev/hda6             906        1032     1020096   83  Linux
/dev/hda7            1033        1097      522081   82  Linux swap / Solaris
/dev/hda8            1098        2314     9775521   83  Linux


Create 3 partitions

[root@client24 ~]# fdisk /dev/hda

The number of cylinders for this disk is set to 4865.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): n
First cylinder (2315-4865, default 2315):
Using default value 2315
Last cylinder or +size or +sizeM or +sizeK (2315-4865, default 4865): +200M

Command (m for help): n
First cylinder (2340-4865, default 2340):
Using default value 2340
Last cylinder or +size or +sizeM or +sizeK (2340-4865, default 4865): +200M

Command (m for help): n
First cylinder (2365-4865, default 2365):
Using default value 2365
Last cylinder or +size or +sizeM or +sizeK (2365-4865, default 4865): +200M




Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.

[root@client24 ~]# partprobe /dev/hda

[root@client24 ~]# fdisk -l

Disk /dev/hda: 40.0 GB, 40020664320 bytes
255 heads, 63 sectors/track, 4865 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1          13      104391   83  Linux
/dev/hda2              14         523     4096575   83  Linux
/dev/hda3             524         778     2048287+  83  Linux
/dev/hda4             779        4865    32828827+   5  Extended
/dev/hda5             779         905     1020096   83  Linux
/dev/hda6             906        1032     1020096   83  Linux
/dev/hda7            1033        1097      522081   82  Linux swap / Solaris
/dev/hda8            1098        2314     9775521   83  Linux
/dev/hda9            2315        2339      200781   83  Linux
/dev/hda10           2340        2364      200781   83  Linux
/dev/hda11           2365        2389      200781   83  Linux

Create Physical Volumes

[root@client24 ~]# pvcreate /dev/hda9 /dev/hda10 /dev/hda11
  Physical volume "/dev/hda9" successfully created
  Physical volume "/dev/hda10" successfully created
  Physical volume "/dev/hda11" successfully created

To view Physical Volumes

[root@client24 ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/hda9
  VG Name               vg1
  PV Size               196.08 MB / not usable 4.08 MB
  Allocatable           yes (but full)
  PE Size (KByte)       4096
  Total PE              48
  Free PE               0
  Allocated PE          48
  PV UUID               5r8qvn-GF0k-NAfo-Rhqc-I3Qn-ZWws-zLCvks
 
  --- Physical volume ---
  PV Name               /dev/hda10
  VG Name               vg1
  PV Size               196.08 MB / not usable 4.08 MB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              48
  Free PE               21
  Allocated PE          27
  PV UUID               ys5Wd9-YiQ5-mM7c-sjrt-Mcwb-35oF-8mFyDW
 
  --- Physical volume ---
  PV Name               /dev/hda11
  VG Name               vg1
  PV Size               196.08 MB / not usable 4.08 MB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              48
  Free PE               48
  Allocated PE          0
  PV UUID               5U81jh-Uddd-0giT-GYUT-pkvu-3MK3-KNkZJi
 
To create Volume Group

[root@client24 ~]# vgcreate vg1 /dev/hda9 /dev/hda10 /dev/hda11
  Volume group "vg1" successfully created

To display Volume Group Information.

[root@client24 ~]# vgdisplay
  --- Volume group ---
  VG Name               vg1
  System ID          
  Format                lvm2
  Metadata Areas        3
  Metadata Sequence No  2
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               0
  Max PV                0
  Cur PV                3
  Act PV                3
  VG Size               576.00 MB
  PE Size               4.00 MB
  Total PE              144
  Alloc PE / Size       75 / 300.00 MB
  Free  PE / Size       69 / 276.00 MB
  VG UUID               P1zXt6-yBWW-SoUq-ZeF1-K7pf-Z69D-GVz8Up
 
To create logical Volume

[root@client24 ~]# lvcreate vg1 -L +300M -n lv1
  Logical volume "lv1" created





To view Logical Volume Information.

[root@client24 ~]# lvdisplay
  --- Logical volume ---
  LV Name                /dev/vg1/lv1
  VG Name                vg1
  LV UUID                ZvsfPh-Ve0c-y4Qa-VUYy-HbdR-lG3G-66703a
  LV Write Access        read/write
  LV Status              available
  # open                 0
  LV Size                300.00 MB
  Current LE             75
  Segments               2
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:0
 
[root@client24 ~]#

Format the Logical Volume

[root@client24 ~]# mkfs.ext3 /dev/vg1/lv1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
102400 inodes, 409600 blocks
20480 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=67633152
50 block groups
8192 blocks per group, 8192 fragments per group
2048 inodes per group
Superblock backups stored on blocks:
        8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409

Writing inode tables: done                          
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 20 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

[root@client24 ~]# mkdir /mylvm

[root@client24 ~]# mount /dev/vg1/lv1 /mylvm

[root@client24 ~]# mount
/dev/hda3 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/hda1 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
/dev/hda5 on /home type ext3 (rw)
/dev/hda2 on /usr type ext3 (rw)
/dev/hda6 on /var type ext3 (rw)
/dev/hda8 on /dada type ext3 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
/dev/mapper/vg1-lv1 on /mylvm type ext3 (rw)


To resize the Logical Volume

[root@client24 ~]# lvresize -L +100M /dev/vg1/lv1

Extending logical volume lv1 to 400.00 MB
Logical volume lv1 successfully resized


[root@client24 ~]# lvdisplay
  --- Logical volume ---
  LV Name                /dev/vg1/lv1
  VG Name                vg1
  LV UUID                ZvsfPh-Ve0c-y4Qa-VUYy-HbdR-lG3G-66703a
  LV Write Access        read/write
  LV Status              available
  # open                 0
  LV Size                400.00 MB
  Current LE             100
  Segments               3
  Allocation             inherit
  Read ahead sectors     0
  Block device           253:0
 
[root@client24 ~]# cd /mylvm

[root@client24 mylvm]# ls
lost+found

[root@client24 mylvm]# touch file1 file2 file3

[root@client24 mylvm]# mkdir hyd sec

[root@client24 mylvm]# ls
file1  file2  file3  hyd  lost+found  sec

To remove logical Volume

[root@client24 ~]# cd

[root@client24 ~]# umount /mylvm

[root@client24 ~]# lvremove /dev/vg1/lv1

Do you really want to remove active logical volume "lv1"? [y/n]: y
Logical volume "lv1" successfully removed





[root@client24 ~]# fdisk /dev/hda

The number of cylinders for this disk is set to 4865.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): n
First cylinder (2390-4865, default 2390): +300M
Value out of range.
First cylinder (2390-4865, default 2390): w
First cylinder (2390-4865, default 2390):
Using default value 2390
Last cylinder or +size or +sizeM or +sizeK (2390-4865, default 4865): +300M

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
[root@client24 ~]# partprobe /dev/hda


[root@client24 ~]# fdisk -l

Disk /dev/hda: 40.0 GB, 40020664320 bytes
255 heads, 63 sectors/track, 4865 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1          13      104391   83  Linux
/dev/hda2              14         523     4096575   83  Linux
/dev/hda3             524         778     2048287+  83  Linux
/dev/hda4             779        4865    32828827+   5  Extended
/dev/hda5             779         905     1020096   83  Linux
/dev/hda6             906        1032     1020096   83  Linux
/dev/hda7            1033        1097      522081   82  Linux swap / Solaris
/dev/hda8            1098        2314     9775521   83  Linux
/dev/hda9            2315        2339      200781   83  Linux
/dev/hda10           2340        2364      200781   83  Linux
/dev/hda11           2365        2389      200781   83  Linux
/dev/hda12           2390        2426      297171   83  Linux






[root@client24 ~]# pvcreate /dev/hda12

  Physical volume "/dev/hda12" successfully created

To extend the volume group.

[root@client24 ~]# vgextend vg1 /dev/hda12
  Volume group "vg1" successfully extended

[root@client24 ~]# vgdisplay

  --- Volume group ---
  VG Name               vg1
  System ID          
  Format                lvm2
  Metadata Areas        4
  Metadata Sequence No  5
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                0
  Open LV               0
  Max PV                0
  Cur PV                4
  Act PV                4
  VG Size               864.00 MB
  PE Size               4.00 MB
  Total PE              216
  Alloc PE / Size       0 / 0
  Free  PE / Size       216 / 864.00 MB
  VG UUID               P1zXt6-yBWW-SoUq-ZeF1-K7pf-Z69D-GVz8Up
 

Looking forward for your suggestions.. please feel free to write to me.. Your help would definitely help to improve our blog. Chetan Yadav