emctl

export oracle_uniqname="global SID Name"

[oracle@mac dbs]$ emctl start dbconsole


check this doc for more details.

http://www.appsdba.com/blog/?p=305

[oracle@wtu ~]$ echo $ORACLE_SID
orcl
[oracle@wtu ~]$ echo $ORACLE_UNQNAME

[oracle@wtu ~]$

the output is blank

Also

[oracle@wtu ~]$ emctl start dbconsole
OC4J Configuration issue. /u01/app/oracle/product/112/oc4j/j2ee/OC4J_DBConsole_wtu.localdomain_orcl not found.
[oracle@wtu ~]$ echo $ORACLE_SID
orcl
[oracle@wtu ~]$ echo $ORACLE_UNQNAME

[oracle@wtu ~]$

set the ORACLE_UNQNAME

[oracle@wtu ~]$export ORACLE_UNQNAME=orcl

then try to start the dbconsonel.

This is what I did based on the link..

at this point what shoud I do..

[oracle@mac db_1]$ cd sysman
[oracle@mac sysman]$ ls
admin  config  emd     install  jlib  log   recv
bam    emcli   emdrep  j2ee     lib   prov
[oracle@mac sysman]$ cd ..
[oracle@mac db_1]$ ls
apex         deinstall         jdev     OPatch       scheduler
assistants   demo              jdk      opmn         slax
bin          diagnostics       jlib     oracore      sqldeveloper
ccr          dv                ldap     oraInst.loc  sqlj
cdata        emcli             lib      ord          sqlplus
cfgtoollogs  has               log      oui          srvm
clone        hs                md       owb          sysman
config       ide               mesg     owm          timingframework
crs          install           mgw      perl         ucp
csmig        install.platform  network  plsql        uix
css          instantclient     nls      precomp      utl
ctx          inventory         oc4j     racg         wwg
cv           j2ee              odbc     rdbms        xdk
dbs          javavm            olap     relnotes
dc_ocm       jdbc              ons      root.sh
[oracle@mac db_1]$ cd bin
[oracle@mac bin]$ emctl start dbconsole
The following exception occurred:
java.net.UnknownHostException: orcl.localdomain: orcl.localdomain
        at java.net.InetAddress.getAllByName0(InetAddress.java:1145)
        at java.net.InetAddress.getAllByName(InetAddress.java:1072)
        at java.net.InetAddress.getAllByName(InetAddress.java:1008)
        at java.net.InetAddress.getByName(InetAddress.java:958)
        at oracle.sysman.emd.targetIntg.agent.AgentTargetInstaller.getLocalHost(AgentTargetInstaller.java:4289)
        at oracle.sysman.emd.targetIntg.agent.AgentTargetInstaller.printLocalHost(AgentTargetInstaller.java:4252)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at oracle.sysman.emd.targetIntg.Util$DefaultIntegrationMethod.execute(Util.java:598)
        at oracle.sysman.emd.targetIntg.TargetInstaller.execute_(TargetInstaller.java:167)
        at oracle.sysman.emd.targetIntg.TargetInstaller.execute(TargetInstaller.java:155)
        at oracle.sysman.emSDK.conf.TargetInstaller.printLocalHost(TargetInstaller.java:2364)
        at oracle.sysman.emSDK.conf.TargetInstaller.main(TargetInstaller.java:3290)
Although there was an exception it might be possible for the program to continue.
OC4J Configuration issue. /u01/app/oracle/product/11.2.0/db_1/oc4j/j2ee/OC4J_DBConsole_orcl.localdomain_orcl not found.
[oracle@mac bin]$ emca -config dbcontrol db -repos create

STARTED EMCA at Sep 11, 2012 11:22:25 PM
EM Configuration Assistant, Version 11.2.0.0.2 Production
Copyright (c) 2003, 2005, Oracle.  All rights reserved.

Enter the following information:
Database SID: orcl
log4j:ERROR No appenders could be found for category (emSDK.config).
log4j:ERROR Please initialize the log4j system properly.
Exception in thread "main" oracle.sysman.emcp.exception.DatabaseUnavailableException: Database instance unavailable.
        at oracle.sysman.emcp.DatabaseChecks.throwDBUnavailableException(DatabaseChecks.java:151)
        at oracle.sysman.emcp.DatabaseChecks.checkDbAvailabilityImpl(DatabaseChecks.java:139)
        at oracle.sysman.emcp.DatabaseChecks.checkDbAvailability(DatabaseChecks.java:163)
        at oracle.sysman.emcp.DatabaseChecks.getDbServiceName(DatabaseChecks.java:582)
        at oracle.sysman.emcp.EMConfigAssistant.performConfiguration(EMConfigAssistant.java:1267)
        at oracle.sysman.emcp.EMConfigAssistant.statusMain(EMConfigAssistant.java:573)
        at oracle.sysman.emcp.EMConfigAssistant.main(EMConfigAssistant.java:521)
[oracle@mac bin]$ export LD_LIBRARY_PATH=$ORACLE_HOME/lib32
[oracle@mac bin]$ export LD_LIBRARY_PATH_64=$ORACLE_HOME/lib
[oracle@mac bin]$ cd $ORACLE_HOME/network/lib
[oracle@mac lib]$ make -f ins_net_client.mk client_sharedlib
/u01/app/oracle/product/11.2.0/db_1/bin/genclntsh
/u01/app/oracle/product/11.2.0/db_1/bin/genagtsh /u01/app/oracle/product/11.2.0/db_1/lib/libagtsh.so 1.0
[oracle@mac lib]$ relink all
writing relink log to: /u01/app/oracle/product/11.2.0/db_1/install/relink.log

[oracle@mac lib]$
[oracle@mac lib]$ emctl start dbconsole
The following exception occurred:
java.net.UnknownHostException: orcl.localdomain: orcl.localdomain
        at java.net.InetAddress.getAllByName0(InetAddress.java:1145)
        at java.net.InetAddress.getAllByName(InetAddress.java:1072)
        at java.net.InetAddress.getAllByName(InetAddress.java:1008)
        at java.net.InetAddress.getByName(InetAddress.java:958)
        at oracle.sysman.emd.targetIntg.agent.AgentTargetInstaller.getLocalHost(AgentTargetInstaller.java:4289)
        at oracle.sysman.emd.targetIntg.agent.AgentTargetInstaller.printLocalHost(AgentTargetInstaller.java:4252)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at oracle.sysman.emd.targetIntg.Util$DefaultIntegrationMethod.execute(Util.java:598)
        at oracle.sysman.emd.targetIntg.TargetInstaller.execute_(TargetInstaller.java:167)
        at oracle.sysman.emd.targetIntg.TargetInstaller.execute(TargetInstaller.java:155)
        at oracle.sysman.emSDK.conf.TargetInstaller.printLocalHost(TargetInstaller.java:2364)
        at oracle.sysman.emSDK.conf.TargetInstaller.main(TargetInstaller.java:3290)
Although there was an exception it might be possible for the program to continue.
OC4J Configuration issue. /u01/app/oracle/product/11.2.0/db_1/oc4j/j2ee/OC4J_DBConsole_orcl.localdomain_orcl not found.
[oracle@mac lib]$ emctl status dbconsole
The following exception occurred:
java.net.UnknownHostException: orcl.localdomain: orcl.localdomain
        at java.net.InetAddress.getAllByName0(InetAddress.java:1145)
        at java.net.InetAddress.getAllByName(InetAddress.java:1072)
        at java.net.InetAddress.getAllByName(InetAddress.java:1008)
        at java.net.InetAddress.getByName(InetAddress.java:958)
        at oracle.sysman.emd.targetIntg.agent.AgentTargetInstaller.getLocalHost(AgentTargetInstaller.java:4289)
        at oracle.sysman.emd.targetIntg.agent.AgentTargetInstaller.printLocalHost(AgentTargetInstaller.java:4252)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)
        at oracle.sysman.emd.targetIntg.Util$DefaultIntegrationMethod.execute(Util.java:598)
        at oracle.sysman.emd.targetIntg.TargetInstaller.execute_(TargetInstaller.java:167)
        at oracle.sysman.emd.targetIntg.TargetInstaller.execute(TargetInstaller.java:155)
        at oracle.sysman.emSDK.conf.TargetInstaller.printLocalHost(TargetInstaller.java:2364)
        at oracle.sysman.emSDK.conf.TargetInstaller.main(TargetInstaller.java:3290)
Although there was an exception it might be possible for the program to continue.
OC4J Configuration issue. /u01/app/oracle/product/11.2.0/db_1/oc4j/j2ee/OC4J_DBConsole_orcl.localdomain_orcl not found.
[oracle@mac lib]$ cd ..
[oracle@mac network]$ ls
admin  doc  install  jlib  lib  log  mesg  tools  trace
[oracle@mac network]$ cd ..
[oracle@mac db_1]$ ls
apex         deinstall         jdev     OPatch       scheduler
assistants   demo              jdk      opmn         slax
bin          diagnostics       jlib     oracore      sqldeveloper
ccr          dv                ldap     oraInst.loc  sqlj
cdata        emcli             lib      ord          sqlplus
cfgtoollogs  has               log      oui          srvm
clone        hs                md       owb          sysman
config       ide               mesg     owm          timingframework
crs          install           mgw      perl         ucp
csmig        install.platform  network  plsql        uix
css          instantclient     nls      precomp      utl
ctx          inventory         oc4j     racg         wwg
cv           j2ee              odbc     rdbms        xdk
dbs          javavm            olap     relnotes
dc_ocm       jdbc              ons      root.sh
[oracle@mac db_1]$ cd oc4j/
[oracle@mac oc4j]$ ls
ant          diagnostics  javavm  lib          rdbms        sqlj         xqs
bin          j2ee         jdbc    opmn         Readme.txt   toplink
cfgtoollogs  javacache    jlib    product.xml  sainventory  webservices
[oracle@mac oc4j]$ cd j2ee/
[oracle@mac j2ee]$ ls
deploy_db_wf.ini   OC4J_DBConsole                      utilities
home               OC4J_Workflow_Component_Container
oc4j_applications  OC4J_Workflow_Management_Container
[oracle@mac j2ee]$ cd OC4J_DBConsole/
[oracle@mac OC4J_DBConsole]$ ls
application-deployments  config  connectors  META-INF
[oracle@mac OC4J_DBConsole]$

Again...

[oracle@wtu j2ee]$ mv OC4J_DBConsole_localhost_orcl OC4J_DBConsole_wtu.localdomain_orcl
[oracle@wtu j2ee]$ ls
deploy_db_wf.ini   OC4J_DBConsole_wtu.localdomain_orcl
home               OC4J_Workflow_Component_Container
oc4j_applications  OC4J_Workflow_Management_Container
OC4J_DBConsole     utilities
[oracle@wtu j2ee]$ emctl start dbconsoleEM Configuration issue. /u01/app/oracle/product/112/wtu.localdomain_orcl not found.
[oracle@wtu j2ee]$ emctl status dbconsole
EM Configuration issue. /u01/app/oracle/product/112/wtu.localdomain_orcl not found.
[oracle@wtu j2ee]$

Any solution for this issue

learnt and resolved in another server