How to extend an existing partition with newly installed hard drive

Question

My hard drive space almost running out, so I installed a new hard drive. My question is, Can I extend an existing patition with newly installed hard drive? e.g. Existing /dev/sda1 /dev/sda2 /dev/sda3

new hard drive /dev/sdb1

Can I extend /dev/sda2 with /dev/sdb1

Thanks in advance!

Answer 1

Since your partitions are showing up as /dev/sda*, that means you're using them directly. A physical partition is inherently part of a single disk, so you can't do it directly.

However, it is possible to create a logical partition that spans multiple physical drives, using LVM. LVM can be set up using the Ubuntu installer, but since you already have a working installation you would need to set it up manually. If you have a separate /home partition, this isn't too difficult:

1. From a live CD, back up your /home partition (e.g. using dd or partimage) to somewhere else.
2. Format the old /home partition and /dev/sdb1 as LVM physical volumes. If you want more space for the root as well, delete the /home partition and recreate it smaller.
3. Add the two physical volumes to an LVM volume group.
4. Create a new LVM volume using all available space.
5. Restore your image onto the new volume. Expand the partition to fill the entire space using resize2fs.
6. Adjust your fstab to tell it to automatically mount your logical partition.

Beware: You will lose the logical partition if either disk fails. Keep good backups.