Hi

I have 2.3 TB storage in myserver (DAS). and I need to partition it in different segment.How can i Partition like this type of huge amount in RHEL AS 5

1. use a filesystem that supports large partition sizes
2. break it into smaller partitions
3. use LVM

But it isn't really clear what you want to do.

I cannot create partition this type of large space with fdisk. When I want to partition with this type of space using fdisk, it creates only 400GB. thats it.

http://en.wikipedia.org/wiki/Comparison_of_file_systems

ext3 can go as high as 32TiB, but you have to specify a larger block size.
ext4 will go as high as a EiB!
reiserfs will go as high as 16TiB
XFS will go to 8EiB and the files can be that big too!

You have to create the partition, then create a filesystem on the partition.
fdisk is supposed to handle as high as 2TiB, but no higher. If you really want to use
partitions, use "parted" and create a gpt disklabel (the standard msdos
won't work either). Note that you won't be able to boot from this disk.

Otherwise, you could try just making the filesystem directly on the whole
device (e.g. mke2fs /dev/sda).