"/dev/random" hangs in java program when server is inactive

Solution Verified - Updated -


  • Reading "/dev/random" hangs in java program
  • entropy is too low to generate enough random numbers
  • Java program hangs as it's waiting on a thread that's continuously in this state trying to generate random numbers:

        "main" prio=10 tid=0x00002aab580e2000 nid=0x6c98 runnable [0x000000004044f000]
           java.lang.Thread.State: RUNNABLE
             at java.io.FileInputStream.readBytes(Native Method)
             at java.io.FileInputStream.read(FileInputStream.java:199)
             at sun.security.provider.NativePRNG$RandomIO.readFully(NativePRNG.java:185)
             at sun.security.provider.NativePRNG$RandomIO.implGenerateSeed(NativePRNG.java:202)
             - locked <0x00002aaad23739a0> (a java.lang.Object)
             at sun.security.provider.NativePRNG$RandomIO.access$300(NativePRNG.java:108)
             at sun.security.provider.NativePRNG.engineGenerateSeed(NativePRNG.java:102)
             at java.security.SecureRandom.generateSeed(SecureRandom.java:495)


  • Red Hat Enterprise Linux 5 - All architectures
  • Red Hat Enterprise Linux 6 - All architectures
  • Java application
  • JBoss Enterprise Application Platform (EAP)
  • Tomcat

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