Device file name /dev/sd? changes across reboots with Red Hat Enterprise Linux 6 and above.

Issue

• On a system with multiple types of HBAs, it is possible for the device file name /dev/sd? to change across reboots.
• This could be reproducible, but depends on configuration. Seems to happen often when mixing SAN storage, but could also occur on MegaRAID+SATA environments.
• If /dev/sd? name is used to specify the drive, it may lead to data loss (mkfs wrong drive), or information leaks (using wrong drive in virtual machines) and other critical problems.