Password file are necessary because oracle needs a way to authenticate
you when you are connecting over a network to a database that has not been
open. If you are connecting to an instance over a network then you have not logged
into the database server, and oracle has no way to verify you.
As the password file are not the database file oracle can read it when when the database is closed. This gives the oracle a way to authenticate you.
You can create a password file using the password file creation utility, ORAPWD.
As the password file are not the database file oracle can read it when when the database is closed. This gives the oracle a way to authenticate you.
You can create a password file using the password file creation utility, ORAPWD.
[FORCE={Y|N}]
[IGNORECASE={Y|N}] [NOSYSDBA={Y|N}]
FILE: Name to assign to the password file.
ENTRIES: (Optional) Maximum number of entries (user
accounts) to permit in the file.
FORCE: (Optional) If y, permits overwriting an existing
password file.
IGNORECASE: (Optional) If y, passwords are treated as
case-insensitive.
NOSYSDBA: (Optional) For Data Vault installations. See the
Data Vault installation guide for your platform for more information.
Note: There are no spaces permitted around the
equal-to (=) character.
The following command creates a password file named orapworcl that
allows up to 30 privileged users with different passwords.
orapwd FILE=orapworcl ENTRIES=30
C:\> orapwd FILE=PWDsid.ora PASSWORD=password
ENTRIES=max_users
In addition to creating the
password file, you must also set the initialization parameter REMOTE_LOGIN_PASSWORDFILE to
the appropriate value. The values recognized are:
·
NONE: No privileged connections are
allowed over nonsecure connections.
·
EXCLUSIVE: (The default) An EXCLUSIVE password
file can be used with only one instance of one database. Only an EXCLUSIVE file
can be modified. Using an EXCLUSIVE password file enables you to add,
modify, and delete users. It also enables you to change the SYS password
with the ALTER USER command.
·
SHARED: A SHARED password file can be used by multiple databases
running on the same server, or multiple instances of an Oracle Real Application
Clusters (RAC) database. A SHARED password file cannot be modified.
This means that you cannot add users to a SHARED password file. Any
attempt to do so or to change the password of SYS or other users with
the SYSDBA or SYSOPER privileges generates an error. All
users needing SYSDBA or SYSOPER system privileges must be
added to the password file when REMOTE_LOGIN_PASSWORDFILE is set to EXCLUSIVE.
After all users are added, you can change REMOTE_LOGIN_PASSWORDFILE to SHARED,
and then share the file.
This option is useful if you are administering
multiple databases or a RAC database.
If REMOTE_LOGIN_PASSWORDFILE is set to EXCLUSIVE or SHARED and
the password file is missing, this is equivalent to setting REMOTE_LOGIN_PASSWORDFILE
to NONE.
Note:
You cannot change the password for SYS if REMOTE_LOGIN_PASSWORDFILE is
set to SHARED. An error message is issued if you attempt to do so.
When you grant SYSDBA or SYSOPER privileges
to a user, that user's name and privilege information are added to the password
file. If the server does not have an EXCLUSIVE password file (that
is, if the initialization parameter REMOTE_LOGIN_PASSWORDFILE is NONE or SHARED,
or the password file is missing), Oracle Database issues an error if you
attempt to grant these privileges.
A user's name remains in the password file only as
long as that user has at least one of these two privileges. If you revoke both
of these privileges, Oracle Database removes the user from the password file.
1.
Set the REMOTE_LOGIN_PASSWORDFILE initialization parameter to EXCLUSIVE.
(This is the default.)
Note: REMOTE_LOGIN_PASSWORDFILE is a static
initialization parameter and therefore cannot be changed without restarting the
database.
2.
Connect with SYSDBA privileges as shown in the following example, and
enter the SYS password when prompted:
CONNECT SYS AS SYSDBA
3.
Start up the instance and create the database if necessary, or mount and open
an existing database.
4.
Create users as necessary. Grant SYSDBA or SYSOPER privileges
to yourself and other users as appropriate.
If your server is using an EXCLUSIVE password
file, use the GRANT statement to grant the SYSDBA or SYSOPER system
privilege to a user:
GRANT SYSDBA TO shaan;
REVOKE SYSDBA FROM shaan;
Because SYSDBA and SYSOPER are the
most powerful database privileges, the WITH ADMIN OPTION is not used
in the GRANT statement. That is, the grantee cannot in turn grant the SYSDBA or SYSOPER privilege
to another user. Only a user currently connected as SYSDBA can grant
or revoke another user's SYSDBA or SYSOPER system
privileges. These privileges cannot be granted to roles, because roles are
available only after database startup.
Use the V$PWFILE_USERS view
to see the users who have been granted SYSDBA or SYSOPER system privileges for
a database.
·
Expand the number of password file users if the password file becomes full
·
Remove the password file
If you receive the file full error (ORA-1996)
when you try to grant SYSDBA or SYSOPER system privileges to a user, you must
create a larger password file and re-grant the privileges to the users.
1.
Identify the users who have SYSDBA or SYSOPER privileges by
querying the V$PWFILE_USERS view.
2.
Delete the existing password file.
3.
Follow the instructions for creating a new password file using the ORAPWD utility
in "Using
ORAPWD". Ensure that the ENTRIES parameter is set to a
number larger than you think you will ever need.
4.
Follow the instructions in "Adding
Users to a Password File".
If you determine that you no
longer require a password file to authenticate users, you can delete the
password file and then optionally reset the REMOTE_LOGIN_PASSWORDFILE initialization
parameter to NONE. After you remove this file, only those users who can be
authenticated by the operating system can perform SYSDBA or SYSOPER database
administration operations.
To make the password invisible
from Command
C:\oracle\ora92\database> attrib +H PWDsid.ora
To make the password invisible
C:\oracle\ora92\database> attrib -H PWDsid.ora
To make the password invisible
from Windows
- Navigate to directory C:\oracle\ora92\database.
- Right-click PWDsid.ora.
- Choose Properties.
- The PWDsid.ora Properties dialog box opens
- In Attributes, check or clear the checkbox next to Hidden.
- Click OK.
To view or hide an invisible
password file:
- Navigate to directory C:\oracle\ora92\database.
- Choose Folder Options from the View main menu.
- Choose the View tab.
- To view an invisible password file, choose Show hidden files and folders.
- To hide an invisible password file, choose Do not show hidden files and folders.
- Click OK.
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