Unity: difference in fdisk format for a lun created by cli vs gui

Hello.

A customer of the mine has created a LUN using Unity GUI to use it for a Oracle disk group.

He's noticed that during the partition creation phase on the host, the first default cylinder is the 5th (see below).

He forced to 1, the partition was created and Oracle ASM could mount the disk without problem.

Instead, using the CLI to create the LUN, the first default cylinder proposed, is the 1st

Why this behaviour?

[root@ica-ractest2 ~]# fdisk /dev/sdt

Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel

Building a new DOS disklabel with disk identifier 0xeaf1456f.

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)

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to

         switch off the mode (command 'c') and change display units to

         sectors (command 'u').

Command (m for help): p

Disk /dev/sdt: 107.4 GB, 107374182400 bytes

255 heads, 63 sectors/track, 13054 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 8192 bytes / 33553920 bytes

Disk identifier: 0xeaf1456f

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): n

Command action

   e   extended

   p   primary partition (1-4)

p

Partition number (1-4): 1

First cylinder (1-13054, default 5): 1

Last cylinder, +cylinders or +size{K,M,G} (1-13054, default 13054):

Using default value 13054

Command (m for help): p

Disk /dev/sdt: 107.4 GB, 107374182400 bytes

255 heads, 63 sectors/track, 13054 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 8192 bytes / 33553920 bytes

Disk identifier: 0xeaf1456f

   Device Boot      Start         End      Blocks   Id  System

/dev/sdt1               1       13054   104856223+  83  Linux

Partition 1 does not start on physical sector boundary.

Command (m for help): w

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

Thanks