Terminology and Basics - Oracle Enterprise Manager 12c Command-Line Interface - page 31

Listing 3-7. Executing the setup function in interactive mode
emcli>status()
Oracle Enterprise Manager 12c EMCLI with Scripting option Version 12.1.0.3.0.
Copyright (c) 1996, 2013 Oracle Corporation and/or its affiliates. All rights reserved.
Verb Jars Home (EMCLI_VERBJAR_DIR) : /u01/app/oracle/product/12.1.0/mw_1/oms/bin/bindings/
default/.emcli
EMCLI Home (EMCLI_INSTALL_HOME) : /u01/app/oracle/product/12.1.0/mw_1/oms/bin
EMCLI Version : 12.1.0.3.0
Java Home : /u01/app/oracle/product/12.1.0/mw_1/jdk16/jdk/jre
Java Version : 1.6.0_43
Log file (EMCLI_LOG_LOC) : CONSOLE
Log level (EMCLI_LOG_LEVEL) : SEVERE
EM URL (EMCLI_OMS_URL) : NOT SET
EM user (EMCLI_USERNAME) : NOT SET
Auto login (EMCLI_AUTOLOGIN) : false
Trust all certificates (EMCLI_TRUSTALL) : false
Once the setup is complete and a valid Enterprise Manager has been authenticated, EM CLI will be ready to
carry out tasks against EM. Setup is often where problems can be found, especially during the initial setup. For example,
you may not know that the port used by EM is blocked between the server on which EM CLI was installed and the OMS.
The setup process will reveal this fact. Once a connection has been established with a successful login, the
EM CLI setup process is complete.
Communication
A number of tasks can be accomplished with either EM CLI or EMCTL. The choice of which tool to use will depend on
a number of factors, such as which tool is available to use or which is more efficient for a particular task. The method
in which the tool will interface with Enterprise Manager may be an additional factor to consider.
EM CLI
EM CLI is a client of the Oracle Management Server (OMS) just as SQL*plus is a client of the database. The Enterprise
Manager OMS installation includes an installation of EM CLI. The EM CLI executable is located in the OMS home
directory, <OMS_HOME>/bin/emctl . EM CLI communicates with the OMS using HTML through the same port and URL
that is used to access the Enterprise Manager graphical interface.
A network trace run on the port used for HTTP communication between EM CLI and Enterprise Manager would
show that all of the requests from EM CLI are GET and POST requests via HTTP. These are the same requests that come
from the GUI console when establishing a logon.
The way EM CLI interfaces with Enterprise Manager allows it to connect from any location where a network
connection can be established to the IP and port of the OMS, which gives EM CLI a distinct advantage over EMCTL in
cases where the commands need to be run from a server other than the one hosting the OMS agent.
EMCTL
EMCTL communicates directly with the agent with which it is installed. EMCTL will only communicate with its own
agent, even when other agents are running on the same server.