The OS will scan each LUN in the FC SAN when SAN Boot function is enabled on FC HBA card and the server connected to FC SAN. The time of scaning will depend on the number of the LUN in FC SAN. The system will try to boot from FC SAN first, then try to boot from local disk after boot failed from FC SAN. People may think the system can not be started if the LUN scan takes a long time.
Disable the SAN Boot function on FC HBA card, below is the operation guide.
（1） Restart the server, enter the HBA configuration menu according to the prompt on screen(Press CTRL + B for Brocade HBA card for example), please check the below picture.
（2） Set the “BIOS” field as “Disable”, then press ALT + S to save the configuration and exit.
Solution 2: (only for RH5485)
Enter BIOS and set the first boot option as 'Legacy Only'.