How to Overcome 18 Common Pitfalls When Installing Oracle Enterprise Manager Grid Control 11g

Overview

The article documents a full installation of Oracle Enterprise Manager (OEM) Grid Control (GC) 11g on a Red Hat 6.4, 64‑bit server, covering prerequisite software, database creation, WebLogic setup, GC deployment, and agent configuration, while highlighting numerous pitfalls and their resolutions.

Prerequisites

Operating system: Red Hat 6.4 (64‑bit)

Database: Oracle 11.2.0.4 (p13390677_112040_*.zip)

WebLogic: 10.3.2 (wls1032_linux32.bin)

GC binaries: GridControl_11.1.0.1.0_*.zip (downloaded from alternative sources)

Pitfall 1 – Installation Media

Ensure the correct OS version, database zip files, WebLogic installer, and GC zip files are available. Example commands: yum install glibc.i686 Install missing 32‑bit glibc for the 32‑bit WebLogic binary.

Pitfall 2 – WebLogic Installation

Running ./wls1032_linux32.bin may show Unable to instantiate GUI ; continue in console mode. Set a custom Middleware Home path when prompted, e.g. /u01/app/oracle/Middleware.

Pitfall 3 – Database Parameters

Before installing GC, adjust the following initialization parameters to meet minimum requirements:

alter system set session_cached_cursors=201 scope=spfile;</code>
<code>alter system set job_queue_processes=11 scope=spfile;</code>
<code>alter system set open_cursors=301;</code>
<code>alter system set log_buffer=10485760 scope=spfile;</code>
<code>alter system set processes=501 scope=spfile;

Pitfall 4 – Middleware Home Not Recognized

If GC cannot detect the middleware home, verify that /etc/hosts contains a correct mapping for the host name used during installation (e.g., 127.0.0.1 localhost emrep11).

Pitfall 5 – Database Connectivity Errors

Errors such as ORA‑01017 often stem from missing password files. Create them with orapwd and use EZCONNECT syntax, e.g., sqlplus sys/oracle@emrep11:1521/EMREP as sysdba.

Pitfall 6 – Password Requirements

OEM passwords must be at least eight characters, start with a letter, and contain at least one digit.

Pitfall 7 – SYSMAN Exists

If the Repository Configuration fails because SYSMAN already exists, drop it with:

/u01/app/oracle/11.2.0.4/dbhome_1/sysman/admin/emdrep/bin/RepManager emrep11 1521 EMREP -action drop

Pitfall 8 – SYSMAN_MDS Exists

Re‑compile invalid objects and delete the SYSMAN_MDS schema using the provided SQL script and admin_recompile_invalid.sql script.

Pitfall 9 – SYSTEM Tablespace Full

Ensure sufficient free space in the SYSTEM tablespace (e.g., allocate at least 500 MB) before proceeding.

Pitfall 10 – Invalid Hostname

The hostname must contain only alphanumeric characters and hyphens; avoid periods. Adjust /etc/sysconfig/network and /etc/hosts accordingly.

Pitfall 11 – Open Files Limit

OEM requires a higher file‑descriptor limit. Set it temporarily with ulimit -n 4096 and permanently in /etc/security/limits.conf:

oracle11g soft nofile 4096
oracle11g hard nofile 65536

Pitfall 12 – GC Console Encoding

Force English language in Chrome or adjust browser language settings to avoid garbled characters.

Pitfall 13 – Port Access

Add firewall exceptions for required ports, e.g.:

vi /etc/sysconfig/iptables
-A INPUT -m state --state NEW -m tcp -p tcp --dport 4903 -j ACCEPT
service iptables restart

Pitfall 14 – Invalid Oracle Home Name

Use an alphanumeric identifier without special characters, e.g., ORACLE_HOME_NAME="APP", when cloning the agent.

Pitfall 15 – Missing staticports.ini

Copy staticports.ini from the OMS server to /u01/app/oracle/Middleware/.gcinstall_temp/. The file contains definitions for all required ports.

Pitfall 16 – Remote Database Not Found

Add the remote host entry to /etc/hosts (e.g., x.x.x.x vm001.cs1cloud.internal) so the OMS can resolve the name.

Pitfall 17 – Using opmnctl vs emctl

For 11g, manage OMS with emctl instead of opmnctl. Set the correct ORACLE_INSTANCE path, e.g., export ORACLE_INSTANCE=/u01/app/oracle/gc_inst/WebTierIH1, then run ./opmnctl status.

Pitfall 18 – Removing an Agent

Delete the agent from the repository with:

exec mgmt_admin.cleanup_agent('vm001.cs1cloud.internal:4903');

Also remove its inventory entry from /u01/app/oracle/oraInventory/ContentsXML/inventory.xml.

Final Steps

After successful installation, verify agent upload and heartbeat using:

./emctl secure agent
./emctl start agent
./emctl upload
./emctl status agent

Confirm that “Last successful upload” and “Last successful heartbeat to OMS” show values.