Issue

• OS cannot recognize DVD disk replace in rescue mode.

• In a customer's operation, all filesystems are restored from backup file on DVD-RAM.
  1. Boot up with RHEL boot disk using USB DVD Drive.
  2. Select appropriate items in "Choose a Language", "Keyboard Type".
  3. Select "Local CDROM" in "Rescue Method" dialog.
  4. Select appropriate items in network setting dialogs.
  5. Replace DVD disk (with bigger capacity than previous) after rescue mode command prompt.
  6. Use the DVD disk (with commands such as fsck or restore) after the drive gets ready.

• After these procedures, we get error message. In the case of fsck, error messages are shown:

  The filesystem size (according to the superblock) is xxxx blocks
  The physical size of the device is yyyy blocks
  Either the superblock or the partition table is likely to be corrupt!
  Abort?

• yyyy is the device size which is acquired by ioctl(BLKGETSIZE64), and it is same as the capacity of previous DVD disk. There are no medium corruption. When we open and close tray of the drive and try to use the command again, we have no error messages.