After experiencing a power reset and restoring power to a server, the server is unable to boot to the Operating System that has been installed onto the iDRAC Vflash. After several minutes, the server is able to boot to vflash and the Operating System to start. The error message is "no boot device available found"
Cause
The Vflash is not accessible until the iDRAC is fully initialized. When there is a power outage, the iDRAC cards is powered off and needs few minutes to initialize. During this time the fans are spinning at their max speed.
Furthermore, installing an operating system to vflash is not supported scenario.
This applies to iDRAC 6, 7, 8 and 9. The iDRAC user guide for 14G will be updated to reflect this.
Supported Configuration
It is possible to boot on a bootable IMG / ISO that is stored on the vflash.
Booting to a partition
You can set an attached vFlash partition as the boot device for the next boot operation.
Before booting a partition, make sure that The vFlash partition contains a bootable image (in the .img or .iso format) to boot from the device.