weblogic nodemanager unknown host problem solved

Requirement to start Admin Server
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example fully qualified hosts name:   inddlvtwlmas.weblogic.net.
find the ip address which is by executing in the  the terminal -
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ifconfig
there you find the ip address  or host ip.
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Syntax;
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sudo has root access.
so root access is given for the Admin account.
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NODEMANAGER
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NODEMANAGER STARTS BY CHECKING THE HOSTS IN THE HOSTS DIRECTORY AND ALSO IN THE NODEMANAGER PROPERTIES .IT ALSO CHECKS THE NODEMANAGER HOST NAME IN THE ADMIN CONSOLE.
SO THERE ARE THREE LOCATIONS
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NodeManager configuration properties from '/apps/weblogic12/user_projects/domains/infra_domain/nodemanager/nodemanager.properties'

sudo bala vi /etc/hosts                                  |   add :hostname at the end of the hosts file
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127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.236.128 inddlvtwlmas01.weblogic.net

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sudo vi /etc/sysconfig/network

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# Created by anaconda

NETWORKING=yes
HOSTNAME=inddlvtwlmas01.weblogic.net
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It asks password of the account. Here bala is my login account of redhat 7.6.This is essential for the configuration to start the Admin server in Web logic before or after installation of Web logic Server.
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Second location is  nodemanager.properties.This is located in the nodemanager folder.
the path

ListenAddress=inddlvtwlmas01.weblogic.net

Third location is Admin Console : change the host name in the machine.
in machines we have node manager configuration  see the below image.

output:correct way of running
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This is the way NODEMANAGER is  Running .

NODEMGR_HOME is already set to /apps/weblogic12/user_projects/domains/infra_domain/nodemanager
CLASSPATH=/apps/jdk/jdk1.8.0_191/lib/tools.jar:/apps/weblogic12/wlserver/server/lib/weblogic.jar:/apps/weblogic12/wlserver/../oracle_common/modules/thirdparty/ant-contrib-1.0b3.jar:/apps/weblogic12/wlserver/modules/features/oracle.wls.common.nodemanager.jar::/apps/weblogic12/wlserver/..:/apps/weblogic12/wlserver/modules/features/oracle.wls.common.grizzly.jar
+ /apps/jdk/jdk1.8.0_191/bin/java -server -Xms32m -Xmx200m -Djdk.tls.ephemeralDHKeySize=2048 -Dcoherence.home=/apps/weblogic12/wlserver/../coherence -Dbea.home=/apps/weblogic12/wlserver/.. -Dweblogic.RootDirectory=/apps/weblogic12/user_projects/domains/infra_domain -Djava.system.class.loader=com.oracle.classloader.weblogic.LaunchClassLoader -Djava.security.policy=/apps/weblogic12/wlserver/server/lib/weblogic.policy -Dweblogic.nodemanager.JavaHome=/apps/jdk/jdk1.8.0_191 weblogic.NodeManager -v
<Dec 18, 2018 5:29:21 AM EST> <INFO> <Loading domains file: /apps/weblogic12/user_projects/domains/infra_domain/nodemanager/nodemanager.domains>
<Dec 18, 2018 5:29:24 AM EST> <INFO> <Loading identity key store: FileName=/apps/weblogic12/user_projects/domains/infra_domain/security/DemoIdentity.jks, Type=jks, PassPhraseUsed=true>
<Dec 18, 2018 5:29:24 AM EST> <INFO> <Loaded NodeManager configuration properties from '/apps/weblogic12/user_projects/domains/infra_domain/nodemanager/nodemanager.properties'>
Node manager v12.2.1.3.0

Configuration settings:

DomainsFile=/apps/weblogic12/user_projects/domains/infra_domain/nodemanager/nodemanager.domains
LogLimit=0
DomainsDirRemoteSharingEnabled=false
AuthenticationEnabled=true
LogLevel=INFO
DomainsFileEnabled=true
ListenAddress=inddlvtwlmas01.weblogic.net
NativeVersionEnabled=true
ProcessDestroyTimeout=20000
ListenPort=5556
LogToStderr=true
weblogic.StartScriptName=startWebLogic.sh
SecureListener=true
LogCount=1
LogAppend=true
weblogic.StopScriptEnabled=false
StateCheckInterval=500
CrashRecoveryEnabled=false
weblogic.StartScriptEnabled=true
LogFile=/apps/weblogic12/user_projects/domains/infra_domain/nodemanager/nodemanager.log
LogFormatter=weblogic.nodemanager.server.LogFormatter
coherence.StartScriptEnabled=false
ListenBacklog=50
NodeManagerHome=/apps/weblogic12/user_projects/domains/infra_domain/nodemanager
RestEnabled=false
weblogic.startup.JavaHome=/apps/jdk/jdk1.8.0_191
weblogic.startup.MW_Home=
coherence.startup.JavaHome=/apps/jdk/jdk1.8.0_191
coherence.startup.MW_Home=

Domain name mappings:

infra_domain -> /apps/weblogic12/user_projects/domains/infra_domain

<Dec 18, 2018 5:29:24 AM EST> <INFO> <12.2.1.3.0>
<Dec 18, 2018 5:29:24 AM EST> <INFO> <Server Implementation Class: weblogic.nodemanager.server.NMServer$ClassicServer.>
<Dec 18, 2018 5:29:25 AM EST> <INFO> <Secure socket listener started on port 5556, host inddlvtwlmas01.weblogic.net/192.168.236.128>