Generate javacore automatically ,threaddumps during hung threads

Add the below custom property to genereate thread dump:

com.ibm.websphere.threadmonitor.dump.java  true

Application servers->server->Server Infrastructure->Administration->Custom property

ADMN0022E: Access is denied for the getProcessType operation on Server MBean because of insufficient or empty credentials

If you get error ADMN0022E while you are trying to issue commands that require username ,password,then there is a problem with password.Check the password has any special character which is not allowed.


Check the deployment logs to see any LDAP error as below is there
[LDAP: error code 49 - Invalid Credentials] to confirm the password is wrong.

Class Loading PARENT_FIRST, PARENT_LAST explained

By default in IBM Websphere Application server the PARENT_FIRST option is selected for
class loading.

Classloadingdelegation Model.








As mentioned in the diagram

if delegation model is set to PARENT_FIRST it will try to load from the application jars which are present in WEB-INF/lib or WEB-INF/classes or  included in shared library references.

If the class expected is not present in the application loader it will look up to it parent until Bootstrap.

So in PARENT_FIRST the look up for classes is always upwards .If a class referenced by Ext loader is present in application level then that class will not be visible and throw exception.

PARENT_LAST is just opposite to PARENT_FIRST it  look for classes downwards  from root classloader.

Change sdk version in Websphere 8

Some software integrating with Websphere will require sdk 7 instead of default sdk 6 .There is
a  script available in profile bin directory to change the sdk version

Displays a list of all SDK names available to the product installation.
i.e. managesdk -listAvailable -verbose

-listEnabledProfile [-profileName profile_name]
Displays a list of all SDK names that specific profile is currently configured to use.
i.e. managesdk -listEnabledProfile -profileName default

-listEnabledProfileAll
Displays a list of all profiles in an installation and the SDK names that each profile is currently configured to use.
i.e. managesdk -listEnabledProfileAll

-enableProfile [-profileName profile_name] [-sdkname sdkName] [-enableServers] [-user user_name] [-password password_value]
Enables a profile to use a specified SDK name.
i.e. managesdk -enableProfile -profileName default -sdkname 1.6_64 -enableServers

-enableProfileAll [-sdkname sdkName] [-enableServers] [-user user_name] [-password password_value]
Enables all profiles in an installatino to use a specified SDK name.
i.e. managesdk -enableProfileAll -sdkname 1.6_64 -enableServers

-getNewProfileDefault
Displays the SDK name currently configured for all profiles created with the manageprofiles command.
i.e. managesdk -getNewProfileDefault

-setNewProfileDefault [-sdkname sdkName]
Changes the SDK name currently configured for all profiles created with the manageprofiles command.
i.e. managesdk -setNewProfileDefault -sdkname 1.6_64

-getCommandDefault
Displays the SDK name that script commands are enabled to use when no profile is specified by the command and when no profile is defaulted by the command.
i.e. managesdk -getCommandDefault

-setCommandDefault [-sdkname sdkName]
Changes the SDK name that script commands are enabled to use when no profile is specified by the command and when no profile is defaulted by the command.
i.e. managesdk -setCommandDefault -sdkname 1.6_64


IBM Reference  

ADMS0005E: The system is unable to generate synchronization request: javax.management.JMRuntimeException: ADMN0022E: Access is denied for the getRepositoryEpoch operation on ConfigRepository MBean because of insufficient or empty credentials.

If you get this error then synchronisation issue is there.Please check node is in sync in WAS console.
The server will not come up if node is not synch .Check for error messages like
Caused by: com.ibm.ejs.EJSException: Could not register with Location Service Daemon, which could only reside in the NodeAgent in SysOut logs.

Restart nodeagent to solve the issue .
The JVM will not come up if nodeagent has issue in registering with local service deamon.