Disk Reading Error - Centos 6.2

[pschaff]

I had no idea of the volume of information you intended to post, or would have directed you to review [url=http://www.centos.org/modules/newbb/viewtopic.php?topic_id=28726&forum=54]Readme First[/url] and use http://pastebin.centos.org. There is really no point in pasting all of that here. It could accompany a bug report at http://bugs.centos.org/ [b]if[/b] requested there.

[sofatiger51]

Part 9:

10:34:06,126 DEBUG : DeviceTree.addUdevDevice: info: {'ID_VENDOR_ID': '1bcf', 'ID_PART_TABLE_TYPE': 'dos', 'ID_USB_INTERFACE_NUM': '00', 'ID_REVISION': '010f', 'UDISKS_PARTITION_SCHEME': 'mbr', 'ID_VENDOR_ENC': 'Hitachi\\x20', 'ID_PATH': 'pci-0000:00:1d.7-usb-0:6:1.0-scsi-0:0:0:0', 'UDISKS_PARTITION_SIZE': '209715200', 'ID_FS_VERSION': '1.0', 'ID_MODEL_ID': '0c31', 'ANACBIN': '/sbin', 'ID_VENDOR': 'Hitachi', 'ID_SERIAL': 'Hitachi_HTS541616J9SA00_FFFACFF0FF000000FB2441FFDFDFFE-0:0', 'UDISKS_PRESENTATION_NOPOLICY': '0', 'UDISKS_PARTITION': '1', 'DEVTYPE': 'partition', 'MINOR': '1', 'ID_FS_UUID_ENC': 'b5c7683b-c9a4-4ce8-9257-866810a18a79', 'MPATH_SBIN_PATH': '/sbin', 'ID_FS_TYPE': 'ext4', 'ID_FS_UUID': 'b5c7683b-c9a4-4ce8-9257-866810a18a79', 'DEVLINKS': '/dev/block/8:1 /dev/disk/by-id/usb-Hitachi_HTS541616J9SA00_FFFACFF0FF000000FB2441FFDFDFFE-0:0-part1 /dev/disk/by-path/pci-0000:00:1d.7-usb-0:6:1.0-scsi-0:0:0:0-part1 /dev/disk/by-uuid/b5c7683b-c9a4-4ce8-9257-866810a18a79', 'SUBSYSTEM': 'block', 'ID_MODEL': 'HTS541616J9SA00', 'UDISKS_PARTITION_TYPE': '0x83', 'ID_SERIAL_SHORT': 'FFFACFF0FF000000FB2441FFDFDFFE', 'ID_USB_INTERFACES': ':080650:', 'ID_INSTANCE': '0:0', 'UDISKS_PARTITION_SLAVE': '/sys/devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda', 'UDISKS_PARTITION_NUMBER': '1', 'UDISKS_PARTITION_ALIGNMENT_OFFSET': '0', 'ID_FS_USAGE': 'filesystem', 'ID_TYPE': 'disk', 'UDISKS_PARTITION_OFFSET': '1048576', 'ID_BUS': 'usb', 'symlinks': ['/dev/block/8:1', '/dev/disk/by-id/usb-Hitachi_HTS541616J9SA00_FFFACFF0FF000000FB2441FFDFDFFE-0:0-part1', '/dev/disk/by-path/pci-0000:00:1d.7-usb-0:6:1.0-scsi-0:0:0:0-part1', '/dev/disk/by-uuid/b5c7683b-c9a4-4ce8-9257-866810a18a79'], 'MAJOR': '8', 'name': 'sda1', 'DEVPATH': '/devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1', 'UDEV_LOG': '3', 'DEVNAME': 'sda1', 'sysfs_path': '/devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1', 'ID_MODEL_ENC': 'HTS541616J9SA00\\x20', 'ID_USB_DRIVER': 'usb-storage'} ; name: sda1 ;
10:34:06,127 DEBUG : scanning sda1 (/devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1)...
10:34:06,127 DEBUG : looking for device 'sda1'...
10:34:06,130 DEBUG : found None
10:34:06,130 DEBUG : sda1 is a partition
10:34:06,132 DEBUG : DeviceTree.addUdevPartitionDevice: name: sda1 ;
10:34:06,132 DEBUG : looking for device 'sda'...
10:34:06,133 DEBUG : found DiskDevice instance (0xa8c060c) --
name = sda status = True parents = []
kids = 1
id = 7
uuid = None format = size = 152627.835938
major = 8 minor = 0 exists = True
sysfs path = /devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda partedDevice =
target size = 0 path = /dev/sda
format args = [] originalFormat = DiskLabel instance (0xa8c07cc) --
type = disklabel name = partition table (MSDOS) status = False
device = /dev/sda uuid = None exists = True
options = None supported = False formattable = True resizable = False
type = msdos partition count = 2 sectorSize = 512
align_offset = 0 align_grain = 2048
partedDisk =
origPartedDisk =
partedDevice =
removable = False partedDevice =
10:34:06,139 DEBUG : DiskDevice.addChild: kids: 1 ; name: sda ;
10:34:06,141 DEBUG : PartitionDevice._setFormat: sda1 ;
10:34:06,142 DEBUG : getFormat('None') returning DeviceFormat instance
10:34:06,144 DEBUG : PartitionDevice._setFormat: sda1 ; current: None ; type: None ;
10:34:06,144 DEBUG : looking up parted Partition: /dev/sda1
10:34:06,146 DEBUG : PartitionDevice.probe: sda1 ; exists: True ;
10:34:06,147 DEBUG : PartitionDevice.getFlag: path: /dev/sda1 ; flag: 1 ;
10:34:06,149 DEBUG : PartitionDevice.flagAvailable: path: /dev/sda1 ; flag: 1 ;
10:34:06,152 DEBUG : PartitionDevice.getFlag: path: /dev/sda1 ; flag: 10 ;
10:34:06,158 DEBUG : PartitionDevice.flagAvailable: path: /dev/sda1 ; flag: 10 ;
10:34:06,158 DEBUG : added partition sda1 (id 13) to device tree
10:34:06,160 DEBUG : DeviceTree.handleUdevDeviceFormat: name: sda1 ;
10:34:06,161 DEBUG : DeviceTree.handleUdevDiskLabelFormat: device: sda1 ;
10:34:06,163 DEBUG : Ext4FS.supported: supported: True ;
10:34:06,164 DEBUG : getFormat('ext4') returning Ext4FS instance
10:34:06,164 DEBUG : device sda1 does not contain a disklabel
10:34:06,164 DEBUG : type detected on 'sda1' is 'ext4'
10:34:06,166 DEBUG : Ext4FS.supported: supported: True ;
10:34:06,237 DEBUG : Ext4FS.supported: supported: True ;
10:34:06,238 DEBUG : getFormat('ext4') returning Ext4FS instance
10:34:06,240 DEBUG : PartitionDevice._setFormat: sda1 ;
10:34:06,242 DEBUG : PartitionDevice._setFormat: sda1 ; current: None ; type: ext4 ;
10:34:06,242 DEBUG : looking up parted Device: /dev/sda1
10:34:06,243 DEBUG : got device: PartitionDevice instance (0xa8c0a4c) --
name = sda1 status = True parents = []
kids = 0
id = 13
uuid = None format = size = 200.0
major = 8 minor = 1 exists = True
sysfs path = /devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda/sda1 partedDevice =
target size = 0 path = /dev/sda1
format args = [] originalFormat = DeviceFormat instance (0xa6a684c) --
type = None name = Unknown status = False
device = /dev/sda1 uuid = None exists = True
options = None supported = False formattable = False resizable = False
grow = None max size = 0 bootable = None
part type = 0 primary = None
partedPartition = disk =
start = 2048 end = 411647 length = 409600
flags =
10:34:06,245 DEBUG : Ext4FS.supported: supported: True ;
10:34:06,247 DEBUG : got format: Ext4FS instance (0xa53ecec) --
type = ext4 name = ext4 status = False
device = /dev/sda1 uuid = b5c7683b-c9a4-4ce8-9257-866810a18a79 exists = True
options = defaults supported = True formattable = True resizable = True
mountpoint = None mountopts = None
label = None size = 200.0 targetSize = 200.0

10:34:06,398 DEBUG : PartitionDevice.teardown: sdb2 ; status: True ;
10:34:06,399 DEBUG : PartitionDevice.teardown: sdb2 ; status: True ;
10:34:06,439 DEBUG : DiskDevice.teardown: sdb ; status: True ;
10:34:06,441 DEBUG : DiskLabel.teardown: device: /dev/sdb ; status: False ; type: disklabel ;
10:34:06,451 DEBUG : DiskLabel.teardown: device: /dev/sdb ; status: False ; type: disklabel ;
10:34:06,483 DEBUG : PartitionDevice.teardown: sdb1 ; status: True ;
10:34:06,485 DEBUG : PartitionDevice.teardown: sdb1 ; status: True ;
10:34:06,524 DEBUG : DiskDevice.teardown: sdb ; status: True ;
10:34:06,526 DEBUG : DiskLabel.teardown: device: /dev/sdb ; status: False ; type: disklabel ;
10:34:06,536 DEBUG : DiskLabel.teardown: device: /dev/sdb ; status: False ; type: disklabel ;
10:34:06,568 DEBUG : PartitionDevice.teardown: sda2 ; status: True ;
10:34:06,569 DEBUG : DeviceFormat.teardown: device: /dev/sda2 ; status: False ; type: None ;
10:34:06,571 DEBUG : DeviceFormat.teardown: device: /dev/sda2 ; status: False ; type: None ;
10:34:06,572 DEBUG : PartitionDevice.teardown: sda2 ; status: True ;
10:34:06,574 DEBUG : DeviceFormat.teardown: device: /dev/sda2 ; status: False ; type: None ;
10:34:06,588 DEBUG : DeviceFormat.teardown: device: /dev/sda2 ; status: False ; type: None ;
10:34:06,620 DEBUG : DiskDevice.teardown: sda ; status: True ;
10:34:06,622 DEBUG : DiskLabel.teardown: device: /dev/sda ; status: False ; type: disklabel ;
10:34:06,631 DEBUG : DiskLabel.teardown: device: /dev/sda ; status: False ; type: disklabel ;
10:34:06,662 DEBUG : OpticalDevice.teardown: sr0 ; status: True ;
10:34:06,702 DEBUG : PartitionDevice.teardown: sda1 ; status: True ;
10:34:06,703 DEBUG : PartitionDevice.teardown: sda1 ; status: True ;
10:34:06,743 DEBUG : DiskDevice.teardown: sda ; status: True ;
10:34:06,745 DEBUG : DiskLabel.teardown: device: /dev/sda ; status: False ; type: disklabel ;
10:34:06,754 DEBUG : DiskLabel.teardown: device: /dev/sda ; status: False ; type: disklabel ;
10:34:06,784 INFO : failed to unlink /etc/mdadm.conf
10:34:06,787 INFO : edd: collected mbr signatures: {'sda': '0x00052dc5', 'sdb': '0xbd7775e3'}
10:34:06,791 DEBUG : Ext4FS.supported: supported: True ;
10:34:06,796 DEBUG : NTFS.supported: supported: False ;
10:34:06,866 DEBUG : HFSPlus.supported: supported: False ;
10:34:06,936 DEBUG : OpticalDevice.mediaPresent: sr0 ; status: True ;
10:34:06,962 DEBUG : Iso9660FS.supported: supported: True ;
10:34:22,007 DEBUG : doAutoPartition()
10:34:22,007 DEBUG : doAutoPart: True
10:34:22,008 DEBUG : clearPartType: 0
10:34:22,008 DEBUG : clearPartDisks: ['sda']
10:34:22,009 DEBUG : autoPartitionRequests: [, , , ]
10:34:22,010 DEBUG : storage.disks: ['sda', 'sdb']
10:34:22,010 DEBUG : storage.partitioned: ['sda', 'sdb']
10:34:22,011 DEBUG : all names: ['sda', 'sda1', 'sda2', 'sdb', 'sdb1', 'sdb2', 'sr0']
10:34:22,011 DEBUG : clearpart: looking at sda2
10:34:22,014 DEBUG : PartitionDevice.getFlag: path: /dev/sda2 ; flag: 6 ;
10:34:22,016 DEBUG : PartitionDevice.flagAvailable: path: /dev/sda2 ; flag: 6 ;
10:34:22,018 DEBUG : PartitionDevice.getFlag: path: /dev/sda2 ; flag: 5 ;
10:34:22,020 DEBUG : PartitionDevice.flagAvailable: path: /dev/sda2 ; flag: 5 ;
10:34:22,021 DEBUG : PartitionDevice.getFlag: path: /dev/sda2 ; flag: 3 ;
10:34:22,023 DEBUG : PartitionDevice.flagAvailable: path: /dev/sda2 ; flag: 3 ;
10:34:22,023 DEBUG : clearpart: looking at sdb2
10:34:22,024 DEBUG : clearpart: looking at sda1
10:34:22,025 DEBUG : clearing sda1
10:34:22,026 DEBUG : partitions: ['sda1', 'sda2']
10:34:22,028 DEBUG : PartitionDevice._setFormat: sda1 ;
10:34:22,028 DEBUG : getFormat('None') returning DeviceFormat instance
10:34:22,030 DEBUG : PartitionDevice._setFormat: sda1 ; current: ext4 ; type: None ;
10:34:22,030 DEBUG : registered action: Destroy Format ext4 on partition sda1 (id 13)
10:34:22,032 DEBUG : PartitionDevice.teardown: sda1 ; status: True ;
10:34:22,034 DEBUG : DeviceFormat.teardown: device: /dev/sda1 ; status: False ; type: None ;
10:34:22,036 DEBUG : PartitionDevice.teardown: sda1 ; status: True ;
10:34:22,046 DEBUG : DeviceFormat.teardown: device: /dev/sda1 ; status: False ; type: None ;
10:34:22,072 DEBUG : removed partition sda1 (id 13) from device tree
10:34:22,074 DEBUG : DiskDevice.removeChild: kids: 2 ; name: sda ;
10:34:22,075 DEBUG : registered action: Destroy Device partition sda1 (id 13)
10:34:22,075 DEBUG : clearpart: looking at sdb1
10:34:22,075 DEBUG : checking whether disk sda has an empty extended
10:34:22,077 DEBUG : extended is None ; logicals is []
10:34:22,077 DEBUG : checking whether disk sdb has an empty extended
10:34:22,077 DEBUG : extended is None ; logicals is []
10:34:22,081 DEBUG : LVMPhysicalVolume.__init__: mountpoint: None ;
10:34:22,081 DEBUG : getFormat('lvmpv') returning LVMPhysicalVolume instance
10:34:22,083 DEBUG : DiskDevice.addChild: kids: 1 ; name: sda ;
10:34:22,085 DEBUG : PartitionDevice._setFormat: req0 ;
10:34:22,087 DEBUG : PartitionDevice._setFormat: req0 ; current: None ; type: lvmpv ;
10:34:22,089 DEBUG : DiskDevice.removeChild: kids: 2 ; name: sda ;
10:34:22,089 DEBUG : added partition req0 (id 14) to device tree
10:34:22,089 DEBUG : registered action: Create Device partition req0 (id 14)
10:34:22,090 DEBUG : getFormat('None') returning DeviceFormat instance
10:34:22,090 DEBUG : registered action: Create Format lvmpv on partition req0 (id 14)
10:34:22,092 DEBUG : Ext4FS.supported: supported: True ;
10:34:22,092 DEBUG : getFormat('ext4') returning Ext4FS instance
10:34:22,094 DEBUG : DiskDevice.addChild: kids: 1 ; name: sda ;
10:34:22,096 DEBUG : PartitionDevice._setFormat: req1 ;
10:34:22,098 DEBUG : PartitionDevice._setFormat: req1 ; current: None ; type: ext4 ;
10:34:22,100 DEBUG : DiskDevice.removeChild: kids: 2 ; name: sda ;
10:34:22,100 DEBUG : added partition req1 (id 15) to device tree
10:34:22,100 DEBUG : registered action: Create Device partition req1 (id 15)
10:34:22,101 DEBUG : getFormat('None') returning DeviceFormat instance
10:34:22,101 DEBUG : registered action: Create Format ext4 on partition req1 (id 15)
10:34:22,101 WARNING : not sanity checking devices because I don't know how yet
10:34:22,103 DEBUG : DiskDevice.setup: sda ; status: True ; orig: False ;
10:34:22,220 DEBUG : removing all non-preexisting partitions ['req0(id 14)', 'req1(id 15)'] from disk(s) ['sda']
10:34:22,221 DEBUG : allocatePartitions: disks=['sda'] ; partitions=['req0(id 14)', 'req1(id 15)']
10:34:22,221 DEBUG : removing all non-preexisting partitions ['req1(id 15)', 'req0(id 14)'] from disk(s) ['sda']
10:34:22,221 DEBUG : allocating partition: req1 ; id: 15 ; disks: ['sda'] ;
boot: True ; primary: False ; size: 500MB ; grow: False ; max_size: 0
10:34:22,221 DEBUG : checking freespace on sda
10:34:22,222 DEBUG : getBestFreeSpaceRegion: disk=/dev/sda part_type=0 req_size=500MB boot=True best=None grow=False
10:34:22,223 DEBUG : current free range is 63-411647 (200MB)
10:34:22,223 DEBUG : current free range is 150378496-312581807 (79200MB)
10:34:22,224 DEBUG : updating use_disk to DiskDevice instance (0xa8c060c) --
name = sda status = True parents = []
kids = 1
id = 7
uuid = None format = size = 152627.835938
major = 8 minor = 0 exists = True
sysfs path = /devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda partedDevice =
target size = 0 path = /dev/sda
format args = [] originalFormat = DiskLabel instance (0xa8c07cc) --
type = disklabel name = partition table (MSDOS) status = False
device = /dev/sda uuid = None exists = True
options = None supported = False formattable = True resizable = False
type = msdos partition count = 1 sectorSize = 512
align_offset = 0 align_grain = 2048
partedDisk =
origPartedDisk =
partedDevice =
removable = False partedDevice = (sda), type: 0
10:34:22,224 DEBUG : new free: parted.Geometry instance --
start: 150378496 end: 312581807 length: 162203312
device: PedGeometry: (150378496-312581807 / 79200MB)
10:34:22,225 DEBUG : new free allows for 0 sectors of growth
10:34:22,225 DEBUG : found free space for bootable request
10:34:22,226 DEBUG : created partition sda1 of 500MB and added it to /dev/sda
10:34:22,228 DEBUG : PartitionDevice._setPartedPartition: req1 ;
10:34:22,229 DEBUG : device req1 new partedPartition parted.Partition instance --
disk: fileSystem: None
number: 1 path: /dev/sda1 type: 0
name: None active: True busy: False
geometry: PedPartition: has path /dev/sda1
10:34:22,232 DEBUG : PartitionDevice._setDisk: sda1 ; new: DiskDevice instance (0xa8c060c) --
name = sda status = True parents = []
kids = 1
id = 7
uuid = None format = size = 152627.835938
major = 8 minor = 0 exists = True
sysfs path = /devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda partedDevice =
target size = 0 path = /dev/sda
format args = [] originalFormat = DiskLabel instance (0xa8c07cc) --
type = disklabel name = partition table (MSDOS) status = False
device = /dev/sda uuid = None exists = True
options = None supported = False formattable = True resizable = False
type = msdos partition count = 2 sectorSize = 512
align_offset = 0 align_grain = 2048
partedDisk =
origPartedDisk =
partedDevice =
removable = False partedDevice = ; old: None ;
10:34:22,234 DEBUG : DiskDevice.addChild: kids: 1 ; name: sda ;
10:34:22,235 DEBUG : PartitionDevice._setPartedPartition: sda1 ;
10:34:22,236 DEBUG : device sda1 new partedPartition parted.Partition instance --
disk: fileSystem: None
number: 1 path: /dev/sda1 type: 0
name: None active: True busy: False
geometry: PedPartition: has path /dev/sda1
10:34:22,237 DEBUG : allocating partition: req0 ; id: 14 ; disks: ['sda'] ;
boot: False ; primary: False ; size: 1MB ; grow: True ; max_size: 0
10:34:22,237 DEBUG : checking freespace on sda
10:34:22,237 DEBUG : getBestFreeSpaceRegion: disk=/dev/sda part_type=0 req_size=1MB boot=False best=None grow=True
10:34:22,238 DEBUG : current free range is 63-411647 (200MB)
10:34:22,238 DEBUG : current free range is 151402496-312581807 (78700MB)
10:34:22,239 DEBUG : evaluating growth potential for new layout
10:34:22,239 DEBUG : calculating growth for disk /dev/sda
10:34:22,241 DEBUG : PartitionDevice._setPartedPartition: req0 ;
10:34:22,242 DEBUG : device req0 new partedPartition parted.Partition instance --
disk: fileSystem: None
number: 3 path: /dev/sda3 type: 0
name: None active: True busy: False
geometry: PedPartition: has path /dev/sda3
10:34:22,245 DEBUG : PartitionDevice._setDisk: sda3 ; new: DiskDevice instance (0xa8c060c) --
name = sda status = True parents = []
kids = 2
id = 7
uuid = None format = size = 152627.835938
major = 8 minor = 0 exists = True
sysfs path = /devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6:1.0/host0/target0:0:0/0:0:0:0/block/sda partedDevice =
target size = 0 path = /dev/sda
format args = [] originalFormat = DiskLabel instance (0xa8c07cc) --
type = disklabel name = partition table (MSDOS) status = False
device = /dev/sda uuid = None exists = True
options = None supported = False formattable = True resizable = False
type = msdos partition count = 3 sectorSize = 512
align_offset = 0 align_grain = 2048
partedDisk =
origPartedDisk =
partedDevice =
removable = False partedDevice = ; old: None ;

[sofatiger51]

Please delete my bug reports. I am sorry that I post so much materials that appeared to be useless to you guys.
I will post at Centos bug report.

Thanks for your help.

[sofatiger51]

Please delete my bug reports as you please. Sorry to bother you and occupy big real estate of this forums.
I will go to bugs/centos.org to file the report.

The long and the short end of the report is that the disk seems to be formatted GPT once for Mac and that could be the cause of my trouble not being able to install Centos.
Be that as it may, I have no problem with Ubuntu installation on the same disk. Aside from Centos, the same disk has problem installing Fedora 16. Maybe my Acer laptop is not good for RHEL related Linux distro.

Thanks for all your help.

[pschaff]

The posts are already here, so deleting them would probably just further confuse the issue, and perhaps someone can spot something useful there. I can't.

Note that you should be able to edit your previous post until the edit window times out - 1 hour IIRC.

Some upstream docs may be relevant:
http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Technical_Notes/index.html

[quote]Installation on large disks (i.e. more than 2TB) on non-EFI platforms may encounter some limitations. Many BIOS systems can only boot disks that contain MSDOS partition tables, which cannot fully address large disks. A GPT partition table can address the full disk, but may not be bootable from BIOS. Consequently, the Red Hat Enterprise Linux installer does not support installing the GRUB bootloader to disks that contain GPT partition tables on non-EFI systems. When installing Red Hat Enterprise Linux 6 on a non-EFI system that contains one or more large disks, create a GPT partition table on each of the disks before proceeding to the storage configuration portion of the install process. Leaving the large disks uninitialized, or using an MSDOS partition table on them, can cause problems when creating partitions using anaconda.
Good luck with your bug report.[/quote]

http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Performance_Tuning_Guide/storage-improvements.html

[quote]Large Boot Drives
Traditional BIOS supports a maximum disk size of 2.2TB. Red Hat Enterprise Linux 6 systems using BIOS can support disks larger than 2.2TB by using a new disk structure called Global Partition Table (GPT). GPT can only be used for data disks; it cannot be used for boot drives with BIOS; therefore, boot drives can only be a maximum of 2.2TB in size. The BIOS was originally created for the IBM PC; while BIOS has evolved considerably to adapt to modern hardware, Unified Extensible Firmware Interface (UEFI) is designed to support new and emerging hardware.
Red Hat Enterprise Linux 6 also supports UEFI, which can be used to replace BIOS (still supported). Systems with UEFI running Red Hat Enterprise Linux 6 allow the use of GPT and 2.2TB (and larger) partitions for both boot partition and data partition.
Important — UEFI for 32-bit x86 systems
Red Hat Enterprise Linux 6 does not support UEFI for 32-bit x86 systems.
Important — UEFI for AMD64 and Intel 64
Note that the boot configurations of UEFI and BIOS differ significantly from each other. Therefore, the installed system must boot using the same firmware that was used during installation. You cannot install the operating system on a system that uses BIOS and then boot this installation on a system that uses UEFI.
Red Hat Enterprise Linux 6 supports version 2.2 of the UEFI specification. Hardware that supports version 2.3 of the UEFI specification or later should boot and operate with Red Hat Enterprise Linux 6, but the additional functionality defined by these later specifications will not be available. The UEFI specifications are available from http://www.uefi.org/specs/agreement/. [/quote]

[sofatiger51]

Thanks for all the information. I really appreciate it very much. New MB has come out with Intel Chipset X79 and UEFI BIOS. Next Windows will be interesting how Microsoft choose to activate their OEM Windows using UEFI.
I have to find a way to install Centos because my longer term goal is to learn Centos Linux with Xen hypervisor. My Acer laptop is not for Centos. I have to shop for a second hard drive around 500 GB so that I can install Centos into my spare desktop capable of running 64 bit OS.

[r_hartman]

[quote]I have to find a way to install Centos because my longer term goal is to learn Centos Linux with Xen hypervisor.[/quote]
TUV, and hence CentOS, has abandoned xen in favor of KVM. CentOS 6 does not have xen-kernels, CentOS 5 has.
KVM is available for 64-bit architecture only, IIRC since CentOS 5.4.

[sofatiger51]

Hi Rene,

Thanks for the information. I visited KVM and very impressed with the possibility. I love learning new things as it keeps your brain cells grow or revitalized.

Regards,

Philip