I see two ways of doing this:
1) using jconsole (if possible)
go in the MBeans tab, select the java.util.logging > Operations > setLoggerLevel
p0 = javax.management.remote.rmi.level, p1 = FINER
click on setLoggerLevel button
2) edit the file logging.properties you can find in the jre/lib directory from the jdk installation you use to run GlassFish
add the following line at the end
javax.management.remote.rmi.level = FINER
Then restart your GlassFish
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