Creating Partition Tables

[onurcipe-oc]

Hi,

1.What if I don't create a partition table on a hard disk drive?
(one of my hard disk drives is not partitioned and I am still able to read/write files)

2.What are the advantages/disadvantages of a partitioned hard disk drive?
(I want to use the hard disk drive for only storage, not for running an operating system)

Thanks,
oc

[Lazydog]

[FONT=Courier New]Hi,

1.What if I don't create a partition table on a hard disk drive?
(one of my hard disk drives is not partitioned and I am still able to read/write files)

If you are reading and writing files then that drive is partitioned most likely as a complete drive.

Run FDISK and look at it.

~ $ /sbin/fdisk /dev/sdc1

The number of cylinders for this disk is set to 25495.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): p

Disk /dev/sdc1: 209.7 GB, 209711706624 bytes
255 heads, 63 sectors/track, 25495 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

     Device Boot      Start         End      Blocks   Id  System
/dev/sdc1p1   *           1          13      104391   83  Linux
/dev/sdc1p2              14       25495   204684165   8e  Linux LVM

Command (m for help): q

2.What are the advantages/disadvantages of a partitioned hard disk drive?
(I want to use the hard disk drive for only storage, not for running an operating system)

Thanks,
oc

That all depends. If you have a large drive and partition it could be easier to manage. With a partition drive you can stop the disk from being completely filled allowing the OS to continue to operate when a partition is full.

[onurcipe-oc]

Thank you Lazydog.
Here is the interesting point.

***
~$ sudo /sbin/fdisk /dev/sda
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xa80fa0ce.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

The device presents a logical sector size that is smaller than
the physical sector size. Aligning to a physical sector (or optimal
I/O) size boundary is recommended, or performance may be impacted.

Command (m for help): m
***

I am now able to read/write files. Under these situations I mustn't be able to read/write files. Am I wrong?

Thanks,
oc

[Lazydog]

Which OS are you running?

[onurcipe-oc]

My OS is Ubuntu (11.10).
Actually in partitioning there are 4 partition schemes which are "MBR", "GUID Partitioning Table", "Don't Partition" and "Apple Partition Map".
My question was exactly that what if I select "Don't Partition" and than format the disk as ext4? When I do it I am able to read/write. However, in the terminal I get that message?

Thanks,
oc

[Lazydog]

Not sure I follow what you are asking me......

What I am reading is you formatted the drive as ext4 so you are able to read/write to the drive.
But not understanding what message you get in a terminal. What are you doing, in the terminal, to get this message?

[onurcipe-oc]

Basically my question was, what if I do not select a partition scheme for a hdd and then format the hdd as ext4.
P.S I am a computer engineering student, I also ask to my professors, It seems there might be a bug in Ubuntu. But again we are not sure, If we understand and solve the problem, I will inform you.

Thanks,
oc