oracle enterprise manager OEM13c installation

 OVERVIEW

in this article I will guide you how to install OEM 13c on redhat enterprise linux 7.8.

1. software requirement

we can download OEM 13c software from :

https://www.oracle.com/enterprise-manager/downloads/cloud-control-downloads.html

em13300_linux64-2.zi

em13300_linux64-3.zi

em13300_linux64-4.zi

em13300_linux64-5.zi

em13300_linux64-6.zi

em13300_linux64.bin

   2. Server requirement

OS	redhat:enterprise_linux:7.8
RAM	12 GB
CPU	8
HDD	80 GB
PACKAGES	-packages for OMS make-3.82-24.el7.x86_64 libXtst-1.2.3-1.el7.x86_64 binutils-2.27-43.base.el7_8.1.x86_64 gcc-4.8.5-39.el7.x86_64 libaio-0.3.109-13.el7.x86_64 glibc-common-2.17-307.el7.1.x86_64 libstdc++-4.8.5-39.el7.x86_64 sysstat-10.1.5-19.el7.x86_64 glibc-2.17-307.el7.1.x86_64 glibc-devel-2.17-307.el7.1.x86_64 glibc-devel-2.17-307.el7.1.i686
set to correct value	cat /etc/sysctl.conf | grep shmmax 4398046511104
	cat /etc/sysctl.conf | grep port_range net.ipv4.ip_local_port_range = 11000 65000

    3. DATABASE REQUIREMENT

 

 You need to create a new database for below configuration.

Change parameter optimizer_adaptive_features to false	SQL*Plus: Release 12.1.0.2.0 Production on Sat Dec 5 11:16:26 2020 Copyright (c) 1982, 2014, Oracle.  All rights reserved. Connected to: Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options SQL> show parameter optimizer_adaptive_features NAME                                 TYPE        VALUE ------------------------------------ ----------- ------------------------------ optimizer_adaptive_features          boolean     FALSE SQL> alter system set optimizer_adaptive_features=FALSE scope=both; System altered.
Comment # in oracle bash_profile	# export PATH export TMP=/tmp export TMPDIR=$TMP #export ORACLE_UNQNAME=orauat #export ORACLE_BASE=/u01/app/oracle #export ORACLE_HOME=$ORACLE_BASE/product/12.1.0/dbhome_1 #export ORACLE_SID=orauat export PATH=/usr/sbin:$PATH export PATH=$ORACLE_HOME/bin:$PATH export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib export CLASSPATH=$ORACLE_HOME/jlib:$ORACLE_HOME/rdbms/jlib
Make required directories	mkdir -p /data/oracle/product/bip/config/ mkdir -p /data/oracle/product/bip/cluster/
Change file permission	chmod 775 em13300_linux64.bin
As Oracle user run installer	./em13300_linux64.bin

4. INSTALLATION STEPS

the installation progress would take few hours to complete.

5 . CONCLUSTION

    basically OEM 13c installation is just few simple steps, we just need to ensure that the Database is the fresh installation, if it is an old database we don't recommend to use that, otherwise you will encounter some error during EM configuration steps. beside that, OEM installation directories must also be clean up if you need to install OEM software again. Good luck for your installation steps!

Redo logs switch too frequently

1. Observation

I do select :

SELECT dat,num FROM
(SELECT TO_CHAR(FIRST_TIME,'DD-MON-YYYY HH24:Mi') dat,
COUNT(1) num
FROM V$LOGHIST
WHERE trunc(FIRST_TIME) = trunc ( SYSDATE )
GROUP BY TO_CHAR(FIRST_TIME,'DD-MON-YYYY HH24:Mi')
HAVING COUNT(1) >= 8
ORDER BY dat desc;

As a result, I 've found that redo logs switch more than 8 every minutes,

2. Get information about DB configuration

set markup html on spool on

SPOOL logswitch.HTML

set echo on

set pagesize 30;

select systimestamp from dual;

select * from v$version;

select name,LOG_MODE from v$database;

select * from v$instance_recovery;

select OPTIMAL_LOGFILE_SIZE from v$instance_recovery;

show parameter log_buffer;

show parameter log_checkpoint_interval;

show parameter log_checkpoint_timeout;

show parameter fast_start_mttr_target;

show parameter archive_lag_target;

show parameter filesystem

show parameter disk

select name,value from v$parameter where name like '%log_archive%' and value <> 'enable';

select name from v$controlfile;

select lg.group#,lg.bytes/1024/1024 mb, lg.status, lg.archived,lf.member

from v$logfile lf, v$log lg

where lg.group# = lf.group#

order by 1, 2;

select to_char(first_time,'YYYY-MON-DD') "Date", to_char(first_time,'DY') day,

to_char(sum(decode(to_char(first_time,'HH24'),'00',1,0)),'999') "00",

to_char(sum(decode(to_char(first_time,'HH24'),'01',1,0)),'999') "01",

to_char(sum(decode(to_char(first_time,'HH24'),'02',1,0)),'999') "02",

to_char(sum(decode(to_char(first_time,'HH24'),'03',1,0)),'999') "03",

to_char(sum(decode(to_char(first_time,'HH24'),'04',1,0)),'999') "04",

to_char(sum(decode(to_char(first_time,'HH24'),'05',1,0)),'999') "05",

to_char(sum(decode(to_char(first_time,'HH24'),'06',1,0)),'999') "06",

to_char(sum(decode(to_char(first_time,'HH24'),'07',1,0)),'999') "07",

to_char(sum(decode(to_char(first_time,'HH24'),'08',1,0)),'999') "08",

to_char(sum(decode(to_char(first_time,'HH24'),'09',1,0)),'999') "09",

to_char(sum(decode(to_char(first_time,'HH24'),'10',1,0)),'999') "10",

to_char(sum(decode(to_char(first_time,'HH24'),'11',1,0)),'999') "11",

to_char(sum(decode(to_char(first_time,'HH24'),'12',1,0)),'999') "12",

to_char(sum(decode(to_char(first_time,'HH24'),'13',1,0)),'999') "13",

to_char(sum(decode(to_char(first_time,'HH24'),'14',1,0)),'999') "14",

to_char(sum(decode(to_char(first_time,'HH24'),'15',1,0)),'999') "15",

to_char(sum(decode(to_char(first_time,'HH24'),'16',1,0)),'999') "16",

to_char(sum(decode(to_char(first_time,'HH24'),'17',1,0)),'999') "17",

to_char(sum(decode(to_char(first_time,'HH24'),'18',1,0)),'999') "18",

to_char(sum(decode(to_char(first_time,'HH24'),'19',1,0)),'999') "19",

to_char(sum(decode(to_char(first_time,'HH24'),'20',1,0)),'999') "20",

to_char(sum(decode(to_char(first_time,'HH24'),'21',1,0)),'999') "21",

to_char(sum(decode(to_char(first_time,'HH24'),'22',1,0)),'999') "22",

to_char(sum(decode(to_char(first_time,'HH24'),'23',1,0)),'999') "23" ,

count(*) Total

from v$log_history

group by to_char(first_time,'YYYY-MON-DD'), to_char(first_time,'DY')

order by to_date(to_char(first_time,'YYYY-MON-DD'),'YYYY-MON-DD')

/

select to_char(COMPLETION_TIME,'DD/MON/YYYY') Day,

trunc(sum(blocks*block_size)/1048576/1024,2) "Size(GB)",count(sequence#) "Total Archives"

from

(select distinct sequence#,thread#,COMPLETION_TIME,blocks,block_size from v$archived_log)

group by to_char(COMPLETION_TIME,'DD/MON/YYYY')

order by to_date(to_char(COMPLETION_TIME,'DD/MON/YYYY'),'DD/MON/YYYY')

;

spool off

set markup html off spool off

3. we got output

SQL> select lg.group#,lg.bytes/1024/1024 mb, lg.status, lg.archived,lf.member

2 from v$logfile lf, v$log lg

3 where lg.group# = lf.group#

4 order by 1, 2;

GROUP# MB STATUS ARC MEMBER

1 50 ACTIVE YES /data01/oradata/TWCMS/redo01.log

1 50 ACTIVE YES /data01/oradata/TWCMS/redo01a.log

2 50 ACTIVE YES /data01/oradata/TWCMS/redo02a.log

2 50 ACTIVE YES /data01/oradata/TWCMS/redo02.log

3 50 ACTIVE YES /data01/oradata/TWCMS/redo03.log

3 50 ACTIVE YES /data01/oradata/TWCMS/redo03a.log

4 50 ACTIVE YES /data01/oradata/TWCMS/redo04.log

4 50 ACTIVE YES /data01/oradata/TWCMS/redo04a.log

5 50 ACTIVE YES /data01/oradata/TWCMS/redo05.log

5 50 ACTIVE YES /data01/oradata/TWCMS/redo05a.log

6 50 CURRENT NO /data01/oradata/TWCMS/redo06a.log

6 50 CURRENT NO /data01/oradata/TWCMS/redo06.log

As a result, redo logs file is very small (50 mb).

4. action to be taken

Reviewed the uploaded files and found the most of the redo logs are always ACTIVE and the no of log switches are at particular times.

This is due to small redo log file size 50MB. I would request you to resize redo log file size to 500MB and monitor your database.