ORACLE board

ERROR: failed to establish dependency between database and diskgroup resource

2014-07-03T15:12:00.004+04:00

Issue:
ERROR: failed to establish dependency between database and diskgroup resource

has found in alert log

Explanation:
This means your database is not configured in clusterware. If you run command "crsctl stat res -t" you will not probably find it in the list.

Solution:
Register your database in clusterware like:
srvctl add database -d -o -p -a "," -r -s
Example:
srvctl add database -d standby -o /u01/app/oracle/product/11.2.0/db_1 -p /u01/app/oracle/product/11.2.0/db_1/dbs/spfilestandby.ora -a "DATA,FRA" -r PHYSICAL_STANDBY -s mount

Oracle Heterogeneous service setup on Linux

2014-05-13T15:36:00.002+04:00

on linux
1. install ODBS drivers
yum install unixODBC
yum install mysql-connector-odbc

2. check if driver is in /etc/odbcinst.ini
# Driver from the mysql-connector-odbc package
# Setup from the unixODBC-libs package
[MySQL]
Description = ODBC for MySQL
Driver = /usr/lib/libmyodbc3_r.so
Setup = /usr/lib/libodbcmyS.so
Driver64 = /usr/lib64/libmyodbc3_r.so
Setup64 = /usr/lib64/libodbcmyS.so
FileUsage = 1

3. add entry into /etc/odbc.ini

[MySQL]

Description = MySQL test database

Trace = Off

TraceFile = stderr

Driver = MySQL

SERVER = 192.168.x.x

USER = root

PASSWORD = *******

PORT = 3306

DATABASE = test

4. test ODBC connection

$ isql -v MySQL

5. configure Oracle heterogeneous service

$ cp /u01/app/oracle/product/11.2.0/db_1/hs/admin/initdg4odbc.ora /u01/app/oracle/product/11.2.0/db_1/hs/admin/initMySQL.ora

6. edit /u01/app/oracle/product/11.2.0/db_1/hs/admin/initMySQL.ora

$ cat ../../hs/admin/initMySQL.ora | grep -v ^"#"

HS_FDS_CONNECT_INFO = MySQL

HS_FDS_TRACE_LEVEL = OFF

HS_FDS_SHAREABLE_NAME = /usr/lib/libodbc.so

HS_LANGUAGE=american_america.we8mswin1252

set ODBCINI=/etc/odbc.ini

7. configure listener

/u01/app/oracle/product/11.2.0/db_1/network/admin/listener.ora

SID_LIST_LISTENER=

...

(SID_DESC=

(SID_NAME=MySQL)

(ORACLE_HOME=/u01/app/oracle/product/11.2.0/db_1)

(PROGRAM=dg4odbc)

)

...

)

...

restart listener

8. add entry into /u01/app/oracle/product/11.2.0/db_1/network/admin/tnsnames.ora

...

mysql =

(DESCRIPTION=

(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521))

(CONNECT_DATA=(SID=MySQL))

(HS=OK)

)

...

9. connect into DB and create database link

SQL> create public database link MY_MYSQL connect to "root" identified by "*******" using 'mysql';

10. test select

SQL> select * from table1@my_mysql;

Oracle Result Cache

2014-04-23T20:18:00.003+04:00

Oracle Result Cache

Available only in Enterprise Edition

Documentation quote:

The result cache stores the results of SQL queries and PL/SQL functions in an area called Result Cache Memory in the shared pool. When these queries and functions are executed repeatedly, the results are retrieved directly from the cache memory. This results in a faster response time. The cached results stored become invalid when data in the dependent database objects is modified. The use of the result cache is database-wide decision. Result cache itself is instance specific and can be sized differently on different instances. To disable the result cache in a cluster, you must explicitly set the RESULT_CACHE_MAX_SIZE initialization parameter to 0 during every instance startup.

How to enable:

check the settings:

SQL> show parameter result_cache

NAME TYPE VALUE
------------------------------------ ----------- -----------
client_result_cache_lag big integer 3000
client_result_cache_size big integer 0
result_cache_max_result integer 10
result_cache_max_size big integer 2G
result_cache_mode string AUTO
result_cache_remote_expiration integer 0

AUTO is meaningless (you can find this setting in SE as default)

RESULT_CACHE_MODE

Property Description

Parameter type String

Syntax RESULT_CACHE_MODE = { MANUAL | FORCE }

Default value MANUAL

Modifiable ALTER SESSION, ALTER SYSTEM

Basic No

SQL> alter system set result_cache_mode=FORCE scope=memory;

SQL> alter system set result_cache_max_size=2G scope=memory;
--> Note: Result Cache is a part of SGA.

How to monitor:
SQL> select DBMS_RESULT_CACHE.status from dual;
STATUS
----------------------------
ENABLED

Generate report:
SQL> set serveroutput on
SQL> execute DBMS_RESULT_CACHE.MEMORY_REPORT(TRUE);
R e s u l t C a c h e M e m o r y R e p o r t
[Parameters]
Block Size = 0 bytes
Maximum Cache Size = 0 bytes (0 blocks)
Maximum Result Size = 0 bytes (0 blocks)
[Memory]
Total Memory = 5184 bytes [0.005% of the Shared Pool]
... Fixed Memory = 5184 bytes [0.005% of the Shared Pool]
....... Memory Mgr = 132 bytes
....... Cache Mgr = 152 bytes
....... Bloom Fltr = 2K bytes
....... State Objs = 2852 bytes
... Dynamic Memory = 0 bytes [0.000% of the Shared Pool]

PL/SQL procedure successfully completed.

RMAN-04014: startup failed: ORA-00845: MEMORY_TARGET not supported on this system

2014-03-28T21:18:00.000+04:00

Issue description
when I did standby creation on other host by using rman duplicate command I've got an error like:
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command at 03/27/2014 15:41:59
RMAN-05501: aborting duplication of target database
RMAN-03015: error occurred in stored script Memory Script
RMAN-04014: startup failed: ORA-00845: MEMORY_TARGET not supported on this system

was really surprised because the standby was configured with less SGA memory than actual primary like

32Gb - SGA* on Production
4 Gb - SGA* on Standby
* - as for MEMORY_TARGET parameter

Reason for the Issue
the problem was in system configuration

[root@sby01 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_sby01-lv_root 53G 18G 34G 35% /
tmpfs 3.0G 30M 2.9G 1% /dev/shm
/dev/vda1 485M 100M 360M 22% /boot
10.1.1.5:/u02 734G 494G 240G 68% /u02

Workaround
[root@sby01 ~]# vi /etc/fstab

#
# /etc/fstab
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/vg_sby01-lv_root / ext4 defaults 1 1
UUID=ae17aee-972b-4f91-806b-f3e33d29a0 /boot ext4 defaults 1 2
/dev/mapper/vg_mtksby01p2-lv_swap swap swap defaults 0 0
tmpfs /dev/shm tmpfs defaults,size=8g 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0

I've allocated 8Gb for tmpfs

[root@sby01 ~]# mount -o remount /dev/shm

Oracle Operating System Statistics

2013-10-31T16:08:00.002+04:00

-- Operating System Statistics

1. CPU Statistics

V$OSSTAT

- view captures machine-level information in the database, making it easier for you to determine if hardware-level resource issues exist.

V$SYSMETRIC_HISTORY

- view shows a one-hour history of the Host CPU Utilization metric, a representation of percentage of CPU usage at each one-minute interval

V$SYS_TIME_MODEL

- view supplies statistics on the CPU usage by the Oracle database. Using both sets of statistics enable you to determine whether the Oracle database or other system activity is the cause of the CPU problems

2. Memory

This command below includes a great deal of detail, including the size of the mapped segment, how much if it is RSS (Real memory), how much of that is shared, the sizes and permissions of the segment. It is the output above that can be ‘compared’ over time to see if a given process is growing, or leaking memory.

$ pmap -x $$

where $$ - process ID

3. Disk I/O Statistics

- Consumer group

V$IOSTAT_CONSUMER_GROUP view captures I/O statistics for all consumer groups that are part of the currently enabled resource plan

- Database file

I/O statistics of database files that are or have been accessed are captured in the V$IOSTAT_FILE view

select * from V$IOSTAT_FILE

- Database function

I/O statistics for database functions (such as the LGWR and DBWR) are captured in the V$IOSTAT_FUNCTION view.

select * from V$IOSTAT_FUNCTION

4. Network Statistics

V$IOSTAT_NETWORK - network I/O statistics

select * from V$IOSTAT_NETWORK

Operating System Data Gathering Tools

Table shows the various tools for gathering operating statistics on *NIX.

Component | UNIX Tool

CPU | sar, vmstat, mpstat, iostat

Memory | sar, vmstat

Disk | sar, iostat

Network |netstat

Oracle streams propagation issue ORA-22636

2013-10-15T14:05:00.002+04:00

Issue

SQL> SELECT DESTINATION_DBLINK,

2 STATUS,

3 ERROR_DATE,

4 ERROR_MESSAGE

5 FROM DBA_PROPAGATION;

DESTINATION_DBLINK

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

ERROR_MESSAGE

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

TO_FORCL.COM

ORA-22636: Message 22636 not found; product=RDBMS; facility=ORA

Diagnostic

Run on both sites

SQL> select * from v$timezone_file;

FILENAME VERSION

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

timezlrg_14.dat 14

SQL> select * from v$timezone_file;

FILENAME VERSION

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

timezlrg_11.dat 11

the versions must be the same

Workaround

Update DST file. Follow the document:

Updating the RDBMS DST version in 11g Release 2 (11.2.0.1 and up) using DBMS_DST (Doc ID 977512.1)

lsnodes.bin: struct size 0

2013-10-15T14:02:00.002+04:00

Issue

cluster nodes list
when trying to get a node list with lsnodes

lsnodes.bin: struct size 0

Solution

Try
cd $ORACLE_GRID (/u01/app/11.2.0/grid/bin)
./olsnodes

sqlplus: error while loading shared libraries

2013-07-29T20:41:00.001+04:00

Issue

sqlplus: error while loading shared libraries: /u01/app/oracle/product/11.2.0/dbhome_1/lib/libclntsh.so.11.1: cannot restore segment prot after reloc: Permission denied

Solution

[root@linux_pc ~]# cat /etc/selinux/config

# This file controls the state of SELinux on the system.

# SELINUX= can take one of these three values:

# enforcing - SELinux security policy is enforced.

# permissive - SELinux prints warnings instead of enforcing.

# disabled - SELinux is fully disabled.

SELINUX=enforcing

# SELINUXTYPE= type of policy in use. Possible values are:

# targeted - Only targeted network daemons are protected.

# strict - Full SELinux protection.

SELINUXTYPE=targeted

# SETLOCALDEFS= Check local definition changes

SETLOCALDEFS=0

[root@linux_pc ~]# cp /etc/selinux/config /etc/selinux/config.bak

[root@linux_pc ~]# vi /etc/selinux/config

[root@linux_pc ~]# cat /etc/selinux/config

# This file controls the state of SELinux on the system.

# SELINUX= can take one of these three values:

# enforcing - SELinux security policy is enforced.

# permissive - SELinux prints warnings instead of enforcing.

# disabled - SELinux is fully disabled.

SELINUX=disabled

# SELINUXTYPE= type of policy in use. Possible values are:

# targeted - Only targeted network daemons are protected.

# strict - Full SELinux protection.

SELINUXTYPE=targeted

echo 0 >/selinux/enforce

PRVF-0002 : Could not retrieve local nodename

2013-07-25T20:33:00.001+04:00

Issue:

While Oracle 12c Installation on Linux (my case OEL6 update 4) you could get an error.

Solution 1:

1. check hostname:

cat /etc/sysconfig/network | grep HOSTNAME

HOSTNAME = test.localdomain

2. check hosts:

cat /etc/hosts

127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4

::1 localhost localhost.localdomain localhost6 localhost6.localdomain6

3. change /etc/hosts like:

127.0.0.1 test test.localdomain

::1 test test.localdomain

4. Run installer

Solution 2:

1. setup system variable like

$ ORACLE_HOSTNAME=test.localdomain
$ export ORACLE_HOSTNAME

How to find which process caused cluster node reboot

2013-06-07T14:18:00.000+04:00

Determining Which Process Caused Reboot
Log File Locations for Processes Causing Reboots.
• oclskd
– /log//client/oclskd.log
• ocssd
– /var/log/messages
– /log//cssd/ocssd.log
• cssdagent
– /log//agent/ohasd/oracss
dagent_root
• cssdmonitor
– /log//agent/ohasd/oracss
dmonitor_root
• hangcheck-timer
– /var/log/messages

Determining Which Process Caused Reboot
First, determine the time of the node reboot by using the uptime command and subtracting the
up time from the current system time. The reboot time will be used when examining log files.
When the OCSSD daemon is responsible for rebooting a node, a message similar to “Oracle
CSSD failure. Rebooting for cluster integrity” is written into the system messages log at
/var/log/messages. The cssd daemon log file that is located at
/log//cssd/ocssd.log may also contain messages similar to
"Begin Dump" or "End Dump" just before the reboot.
If hangcheck-timer is being used, it will provide message logging to the system messages log
when a node restart is initiated by the module. To verify whether this process was responsible
for the node reboot, examine the /var/log/messages file and look for an error message
similar to: "Hangcheck: hangcheck is restarting the machine."
Other useful log files include the Clusterware alert log in /log/
and the lastgasp log in /etc/oracle/lastgasp or /var/opt/oracle/lastgasp.
If no indication of which process caused the reboot can be determined from these files,
additional debugging and tracing may need to be enabled.
Note: The oclsomon and the oprocd background processes have been eliminated in Oracle
Database 11g Release 2.

Standby redologs

2013-06-07T14:17:00.000+04:00

Quote from documentation:

The standby redo logs are populated with redo information as fast as the primary redo logs, rather than waiting for the redo log to be archived and shipped to the standby database. This means that the standby redo log has more current information than the log apply mechanism because it took a "shortcut" and was written to the standby, bypassing the traditional archiving and FTP to the standby database.

Database compatible parameter is set to "11.2.0.0.0" and diskgroup database compatibility attribute is set to "11.2.0.2.0".

2012-11-24T01:51:00.000+04:00

Issue:

Database compatible parameter is set to “11.2.0.0.0” and diskgroup database compatibility attribute is set to “11.2.0.2.0” while creating new database.
Solution
$ cd $ORACLE_HOME/assistants/dbca/templates/
[oracle@db01 templates]$ ls -lha
total 286M
drwxr-xr-x 2 oracle oinstall 4.0K Oct 5 19:03 .
drwxr-xr-x 6 oracle oinstall 4.0K Jun 30 13:01 ..
-rw-r--r-- 1 oracle oinstall 5.0K Oct 5 19:03 Data_Warehouse.dbc
-rw-r--r-- 1 oracle oinstall 5.0K Oct 5 18:56 Data_Warehouse.dbc.bk
-rwxr-xr-x 1 oracle oinstall 21M Sep 22 2011 example01.dfb
-rwxr-xr-x 1 oracle oinstall 1.5M Sep 22 2011 example.dmp
-rw-r--r-- 1 oracle oinstall 4.9K Sep 17 2011 General_Purpose.dbc
-rw-r--r-- 1 oracle oinstall 12K Feb 15 2010 New_Database.dbt
-rwxr-xr-x 1 oracle oinstall 9.3M Sep 22 2011 Seed_Database.ctl
-rwxr-xr-x 1 oracle oinstall 254M Sep 22 2011 Seed_Database.dfb
Edit template
Find
   <InitParamAttributes>
      <InitParams>
         <initParam name="db_name" value=""/>
         <initParam name="dispatchers" value="(PROTOCOL=TCP) (SERVICE={SID}XDB)"/>
         <initParam name="audit_file_dest" value="{ORACLE_BASE}/admin/{DB_UNIQUE_NAME}/adump"/>

Enable DDL Audit

2012-11-24T01:46:00.002+04:00

ALTER SYSTEM SET enable_ddl_logging=TRUE
The result will go to
$ORACLE_BASE/diag/rdbms/db1/DB1/alert
log.xml

ORA-1113 when open database

2012-11-24T01:44:00.000+04:00

Issue:
alter database open
ORA-1113 signalled during: alter database open...
Starting ORACLE instance (normal)
Solution:
startup mount
ALTER DATABASE RECOVER database;
or
Check backup mode
        -- Hot backup status
        SELECT COUNT(*) FROM v$backup WHERE status ='ACTIVE';
        -- Tablespaces in hot backup mode
        SELECT distinct ddf.tablespace_name tablespace_name
        FROM    v$backup vb, DBA_DATA_FILES ddf
        WHERE   vb.status ='ACTIVE' and vb.file# = ddf.file_id;
ALTER TABLESPACE (<tbs_name from the query before>) END BACKUP ;

Agent is Running but Not Ready

2012-11-22T01:08:00.001+04:00

Issue
[oracle@db1 bin]$ ./emctl status agent
Oracle Enterprise Manager 11g Release 1 Grid Control 11.1.0.1.0
Copyright (c) 1996, 2010 Oracle Corporation. All rights reserved.
---------------------------------------------------------------
Agent Version     : 11.1.0.1.0
OMS Version       : 11.1.0.1.0
Protocol Version : 11.1.0.0.0
Agent Home        : /u01/app/oracle/product/EMbase/oracle/MW/agent11g/db1.local
Agent binaries    : /u01/app/oracle/product/EMbase/oracle/MW/agent11g
Agent Process ID : 24910
Parent Process ID : 24865
---------------------------------------------------------------
Agent is Running but Not Ready
Workout
1. emctl stop agent
2. ps -ef | grep emagent
        kill all the process
3. emctl start agent
        Oracle Enterprise Manager 11g Release 1 Grid Control 11.1.0.1.0
        Copyright (c) 1996, 2010 Oracle Corporation. All rights reserved.
        Starting agent ........................................................................................................................... started but not ready.
Solution
emctl unsecure agent
emctl secure agent

How to convert to cluster database

2012-11-22T01:06:00.000+04:00

Convert to cluster DB, make database clustered
1. copy init<>.ora and orapwd<> to another host
2. save spfile to init<>.ora
3. create UNDOTBS2,..
4. add logfiles for thread 2,..
5. assign UNDOTBS for each instance
6. assign instance_number for each instance;

ORA-600 [kkfi.qbcvfr]

2012-06-11T14:08:00.000+04:00

Issue: ORA-600 [kkfi.qbcvfr]

Environment:
RDBMS: 11.2.0.2
OS: Linux 5.5

Error in alert log:
ORA-600 [kkfi.qbcvfr]

Solution:
Patch 9965278

Possible solution (temporary):
alter system/session set "_replace_virtual_columns" = false;
alter system/session set "_disable_function_based_index"=true;
alter system/session set "_fix_control"="6754080:off";
alter system/session set "_fix_control"="8706652:off";

Exadata Storage srvers CellCli and dcli commands

2012-06-11T14:07:00.005+04:00

-- Exadata Starage Servers
CELLCLI
-- use root user to do the work
-- cell configuration files
cellinit.ora, cellip.ora
-- on database server
cellinit.ora - identifies the storage network interface on the database server
        cat /etc/oracle/cell/network-config/cellinit.ora
cellip.ora - identifies the Exadata cells that are accessible to the database server
        cat /etc/oracle/cell/network-config/cellip.ora
-- ASM view to check disk configuration
        V$ASM_DISKGROUP

-- support & diagnostic utility
/opt/oracle.SupportTools
-- usefull commands
cellcli> list cell
cellcli> alter cell restart services all -- restarting RS, CELLSRV, and MS services
cellcli> alter cell {SHUTDOWN | RESTART | STARTUP } services {RS | MS | CELLSRV | ALL}
cellcli> create celldisk all harddisk {interleaving='normal_redundancy'}
cellcli> list celldisk
         CD_00_xdb1cel03         normal
         CD_01_xdb1cel03         normal
cellcli> create griddisk all prefix=data, size=300G
cellcli> list griddisk
         DATA_XDB1_CD_00_xdb1cel03       active
         DATA_XDB1_CD_01_xdb1cel03       active
-- to crate disk group on flash
cellcli> drop flashcache
cellcli> create flashcache all size=100G
cellcli> create griddisk all flashdisk prefix=flash
-- to use all flash cache
cellcli> drop flashcache
cellcli> create flashlog all
cellcli> create flashcache all
------------------------------------------------------------------------------------------------------------------
-- DCLI
-- /opt/oracle/cell/cellsrv/bin/dcli or /usr/local/bin/dcli
dcli -g cell_list date
dcli -c cell01,cell02,cell03 cellcli -e list cell
dcli -g cell_list -x cellclicommands.scl
dcli -g mydbservers -l root -x dbwork.sh
-- cell_list is a file with the list of cells
------------------------------------------------------------------------------------------------------------------
-- IORM I/O Resource Manager
cellcli> list iormplan detail
         name:                   xdb1cel03_IORMPLAN
         catPlan:
         dbPlan:
         objective:              off
         status:                 active
cellcli> alter iormplan objective='balanced'
-- {balanced | off | low_latency | high_throughput | auto}
-- interdatabase Plane Example
cellcli> alter iormplan dbplan =((name=sales_prod, level=1, allocation=80),
                                                (name=finance_prod, level=1, allocation=20),
                                                (name=sales_dev, level=2, allocation=100),
                                                (name=sales_test, level=3, allocation=50),
                                                (name=other, level=3, allocation=50)
                                                ),
                                catplan=''
-- interdatabase Plane and Database Role
cellcli> alter iormplan dbplan =((name=sales1, level=1, allocation=30, role=primary),
                                                (name=sales2, level=1, allocation=35, role=primary),
                                                (name=sales3, level=2, allocation=20, role=standby),
                                                (name=sales4, level=2, allocation=25, role=standby),
                                                (name=other, level=3, allocation=50)
                                                ),
                                catplan=''
-- Flash Memory usage
cellcli> alter iormplan dbplan =((name=oltp, level=1, allocation=80, flashCache=on, flashLog=on),
                                                (name=dss, level=1, allocation=20 limit=50, flashCache=off, flashLog=on),
                                                (name=other, level=2, allocation=100, flashCache=off, flashLog=off),
-- catplan usage
        catplan=((name=INTERACTIVE, level=1, allocation=60),
                         (name=BATCH, level=1, allocation=40)
                        )
-- Activation iormplan
cellcli> alter iormplan active

Alert log from DB side

2012-01-12T14:24:00.004+04:00

--
-- view alert log from DB side
--
-- 0. get info
select * from dba_directories
select * from v$instance
-- 1. create dir
create directory ALERT_LOG as 'G:\SBLSYS\ORADBA\TRACE\BDUMP'
-- 2. create external table
create table alert_log_f (txt varchar2(2000))
organization external (type oracle_loader -- oracle_datapump <-for 10g -- oracle_loader <-for Oracle 9i
default directory ALERT_LOG
--      access parameters (
--          --records delimited by newline
--          nologfile nobadfile
--          fields terminated by 2000 ltrim
--      )
location('alert_orcl.log'))
reject limit unlimited;
drop table alert_log_f
-- 3. check
select * from alert_log_f where lower(txt) like '%ora-%'

How to enable Automatic Memory Management in Oracle 11G

2012-01-11T18:40:00.005+04:00

How to enable Automatic Memory Management in Oracle 11G
1. Set MEMORY_TARGET as (memory_target = sga_target + max(pga_aggregate_target, maximum PGA allocated))
        ALTER SYSTEM SET MEMORY_TARGET = mM SCOPE = SPFILE;
2. Set parameter MEMORY_MAX_TARGET
        ALTER SYSTEM SET MEMORY_MAX_TARGET = nM SCOPE = SPFILE;
Note:   1. n > m
                2. if don't specify MEMORY_TARGET it sets to zero by default
                        and you can manipulate its value dynamicaly not exceeding MEMORY_MAX_TARGET
3. Set SGA_TARGET to zero
        ALTER SYSTEM SET SGA_TARGET = 0;
4. Set PGA_AGGREGATE_TARGET to zero
        ALTER SYSTEM SET PGA_AGGREGATE_TARGET = 0;

Note:
The preceding steps instruct you to set SGA_TARGET and PGA_AGGREGATE_TARGET to zero
so that the sizes of the SGA and instance PGA are tuned up and down as required,
without restrictions. You can omit the statements that set these parameter values to zero
and leave either or both of the values as positive numbers.
In this case, the values act as minimum values for the sizes of the SGA or instance PGA.

How to clear mailbox queue on Linux

2012-01-10T20:08:00.001+04:00

Clear mail queue
1. Login as root
cd /var/spool/mqueue
2. delete all files
rm *

Oracle 11g Flash Cache

2011-12-06T16:09:00.001+04:00

Owerview:
        Oracle Flash Cache looks like a Linux swap or Windows page file.
Requirements:
        Oracle 11g RDBMS must be run on Linux or Solaris
Purpose:
        Reduce db file sequential read waiting
Configuration:
        Set parameter - db_flash_cache_file to the name of the file
        Set parameter - db_flash_cache_size to the size of Flash Cache (must be less than or equal to the physical memory size)

Linux. To delete expiration interval of user password

2011-11-10T19:54:00.001+04:00

Linux. To delete expiration interval of user password
1. login as root
        ls -lh /etc |grep shadow

2. change permition
        chmod 600 /etc/shadow
3. edit shadow
        vi /etc/shadow
                change the string
                        oracle:$1$/lFSo3aP$LHkIxXXxkGtveA8cAjk7//:15197:1:90:7:::
                to
                        oracle:$1$/lFSo3aP$LHkIxXXxkGtveA8cAjk7//:15197:1::7:::
4. change permission back
        chmod 400 /etc/shadow

Disable X Window in Red Hat

2011-10-05T01:39:00.001+04:00

Edit inittab (as root)

vi /etc/inittab

replace line

id:5:initdefault:

with

id:3:initdefault:

Run the commands
init q
init 3

X Window will not start next reboot.

Linux ftp server

2011-07-07T13:34:00.000+04:00

1.find
find -name vsftp*
./vsftpd-2.0.5-16.el5_5.1.x86_64.rpm

2. install
# rpm -Uvh vsftpd-2.0.5-16.el5_5.1.x86_64.rpm

3. configure
Default port: TCP / UDP - 21 and 20
The main configuration file: /etc/vsftpd/vsftpd.conf
Users that are not allowed to login via ftp: /etc/vsftpd/ftpusers
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Open the configuration file, type:
# vi /etc/vsftpd/vsftpd.conf
Turn off standard ftpd xferlog log format:
xferlog_std_format=NO
Turn on verbose vsftpd log format. The default vsftpd log file is /var/log/vsftpd.log:
log_ftp_protocol=YES
Above to directives will enable logging of all FTP transactions. Lock down users to their home directories:
chroot_local_user=YES
Create warning banners for all FTP users:
banner_file=/etc/vsftpd/issue
Create /etc/vsftpd/issue file with a message compliant with the local site policy or a legal disclaimer
-------------------------------------

4. start and stop
Turn on vsftpd on boot:
# chkconfig vsftpd on

/sbin/service vsftpd start
/sbin/service vsftpd stop