Suppose the Disk is /dev/sdb, the second scsi disk,
fdisk /dev/sdb create as many partitions as you need using command n Label them with command t as 8e for making it Linux LVM Write and Exit with the command w.
Format the partitions you require using mkfs command
mkfs -t ext3 -c /dev/sdb1
LVM commands
pvcreate /dev/sdb1 vgextend VolGroup00 /dev/sdb1 lvextend -L 15G /dev/VolGroup00/LogVol00 ;for extending LogVol to 15GB lvextend -L+1G /dev/VolGroup00/LogVol00 ;for adding one more GB to Logical Volume LogVol01 resize2fs /dev/VolGroup00/LogVol00 ;for resizing the Logical Volumes
To increase the storage capacity while keeping the server online, add the disk and then rescan scsi:
echo "- - -" > /sys/class/scsi_host/host0/scan