- Originally the system has one local disk /dev/sda, then connected with a new external storage (a storage array or a fiber-channel or a SAS disk). After the system was booted up, the internal disk on the server were changed to /dev/sdb while the external disks on the fiber storage were now /dev/sda.
- How to control scsi device ordering during boot. For instance, having the local storage be mapped to sd names before the SAN storage. An example of this would /dev/sda being local and /dev/sdb being external.
- scsi order discovery between local RAID and HBA Qlogic
- Sometimes when we reboot a server which take part in cluster (and only this server currently), the boot hang because HBA Qlogic card is seen as scsi0 instead of local RAID and so no boot partition is available.
- Red Hat Enterprise Linux (RHEL) 5
- Red Hat Enterprise Linux (RHEL) 6