On occasion if you are trying to fdisk or mount a USB disk on Solaris 10 you may get an error that says "Cannot open device." For example: # fdisk /dev/rdsk/c2t0d0s2 Cannot open device Things to check:
  • 1. Make sure you are root or have the correct user privilege
  • 2. Try `devfsadm -Cv` to remove any stale disk entries
  • 3. Stop volume management `svcadm disable volfs`


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