Connection to JMX agent is disabled by default on WebLogic 10.x. To enable it add the following JVM parameters to your Weblogic startup scripts.

Unix
Look for file /bin/setDomainEnv.sh

JAVA_OPTIONS="${JAVA_OPTIONS} -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=8888 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false"
export JAVA_OPTIONS

Windows
Look for file /bin/setDomainEnv.cmd

set JAVA_OPTIONS=%JAVA_OPTIONS% -Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=8888 -Dcom.sun.management.jmxremote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false

After server restart you’ll be able to connect remotely via JConsole/VisualVM/etc at host:8888.

ciao