Using gdisk to Partition a Large Disk on CentOS and Configure Automatic Mount

For disks larger than 2 TB you need a GPT partition tool; install gdisk on CentOS 7 with yum install gdisk or on CentOS 6 with yum install gdisk --enablerepo=epel .

Common gdisk commands include -l /dev/sdX to view partitions, ?|m for help, n to create a partition, d to delete, c to change the name, i for detailed info, p to print the table, t to change type, a to toggle bootable, l to list types, o to create a new table, v to verify, q to quit without saving, and w to write changes.

First, list the disks with fdisk -l to identify the new data disk (e.g., /dev/sdc ), then start gdisk on it: gdisk /dev/sdc .

Follow the interactive prompts: press n , choose p for a primary partition, select partition number 1 , accept the default first sector (2048), accept the default last sector, and finally w to write the table.

Synchronize the kernel with partprobe , then format the new partition with mkfs -t ext4 /dev/sdc1 .

Create a mount point, e.g., mkdir /www , and mount the partition: mount /dev/sdc1 /www . Verify the mount with df -TH .

To mount automatically at boot, obtain the partition UUID using blkid /dev/sdc1 , edit /etc/fstab , and add a line such as UUID=your-uuid /www ext4 defaults 0 0 . Save the file, reboot, and confirm the automatic mount with df -TH .