weblogic.utils.AssertionError: ***** ASSERTION FAILED *****[ invalid assignment from 'Object' to 'Object' ]

Solution:

    Use the "-Xint" option to the JVM. This appears to be an issue with the optimization in the Sun JVM 1.4.x versions.

    Alternatively create a .hotspot_compiler file in the working directory of your domain with the content below:

    exclude weblogic/utils/classfile/expr/LocalVariableExpression codeAssign
    exclude weblogic/utils/classfile/expr/AssignStatement <init>

    There is another option and that is to try JRockit JVM

 Issue 2:(Weblogic 10.3)

    <Server subsystem failed. Reason: java.lang.NumberFormatException: null>

Solution:

    Remove: YOUR_DOMAIN/servers/YOUR_ADMIN_SERVER/data/ldap/conf/replicas.prop

 Issue 3:(Weblogic 8.1_SP5)

    Security exception

Solution:

    1) java -cp /opt/bea/8.1_SP5/weblogic81/server/lib/weblogic.jar weblogic.security.utils.AdminAccount weblogic weblogic  ./

    2) cd YOUR_DOMAIN/YOUR_ADMIN_SERVER/ldap

        rm DefaultAuthenticatormyrealmInit.initialized

    3) cp ../../DefaultAuthenticatorInit.ldift .

    4) rm ../../boot.properties

    5) cd ../..

    6) add -Dweblogic.management.username=weblogic -Dweblogic.management.password=weblogic to your start scripts

    Find files in a jar package:

    for i in `ls`; do jar tf $i | grep "KEY_WORD" && echo $i; done

 Skill 2:

    Clean old logs:

    find . -name "*.log" -mtime +1 -exec rm {} \;

    find . -name "*.log" -mmin +30 -exec rm {} \;

Skill 3:

    Compress and uncompress files:

    Compress: tar zcvf FileName.tar.gz DirName

    Uncompress: tar zxvf FileName.tar.gz