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HTTPS (SSL) connection fails with an application running in a Linux virtual machine (1036980)

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With an application running in a Linux virtual machine:

  • An HTTPS connection cannot be established
  • An HTTPS connection times out or works intermittently
  • Application logs show timeouts on /dev/random
  • Necessary entropy is not available to meet required application needs


In Unix and Linux operating systems, /dev/random and /dev/urandom are special files that serve as random number generators. They allow access to environmental noise collected from device drivers and other sources. Inside a virtual machine environment, these devices exhaust their pool of random bits much more quickly than in a physical environment because hardware events are less common in a virtual machine.


To resolve this issue, either:

  • Configure your application to use /dev/urandom instead of /dev/random


  • Replace /dev/random with a symbolic link to /dev/urandom

To replace /dev/random with a symbolic link to /dev/urandom:

  1. Log in to the console of the Linux virtual machine as root.
  2. Back up the current contents of /dev/random with this command:

    mv /dev/random /dev/random.orig

  3. Create the symbolic link from /dev/random to /dev/urandom with this command:

    ln -s /dev/urandom /dev/random

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  • 38 Ratings