GuestOS cannot be booted from virtio disk when IDE disk is added newly in KVM

Issue

• When RHEL6.1 is installed as GuestOS, virtio disk is selected as installed storage by default.
• After that when IDE disk is added as the second storage, OS tries to boot from IDE disk, not virtio disk and either fails to boot with "No bootable disk", or boots whatever OS was in the IDE disk.
• Further, when the IDE disk is removed in KVM, OS is booted from virtio disk once again.
• This problem does not occur when installed storage is changed to IDE disk from virtio disk in GuestOS installed step.
• This problem does not occur on RHEL6.0.