Unable to run su or ps command: Error: /proc must be mounted

Solution Verified - Updated -


  • Unable to execute su and ps commands, getting the following error for non-root users.
$ ps
Error: /proc must be mounted
  To mount /proc at boot you need an /etc/fstab line like:
      proc   /proc   proc    defaults
  In the meantime, run "mount proc /proc -t proc"


$ ps
Error, do this: mount -t proc proc /proc


  • Red Hat Enterprise Linux 7
  • filesystem

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