copied from https://stackoverflow.com/a/42800989/10760563
Before resizing the filesystem by "resize2fs" command you should first resize your partition:
let's list block devices attached to our box:
lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
xvda 202:0 0 16G 0 disk
└─xvda1 202:1 0 8G 0 part /
As you can see /dev/xvda1 is only 8 GiB partition on a 16 GiB device and there are no other partitions on the volume.
step-1) We will use "growpart" to resize 8G partition up to 16G:
# install "cloud-guest-utils" if it is not installed already
apt install cloud-guest-utils
# resize partition
growpart /dev/xvda 1
Let's check the result (you can see /dev/xvda1 is now 16G):
lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
xvda 202:0 0 16G 0 disk
└─xvda1 202:1 0 16G 0 part /
Lots of SO answers suggest to use fdisk with delete / recreate partitions, which is nasty, risky, error-prone process especially when we change boot drive.
step-2) resize file system to grow all the way to fully use new partition space
# Check before resizing ("Avail" shows 1.1G):
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/xvda1 7.8G 6.3G 1.1G 86% /
# resize filesystem
resize2fs /dev/xvda1
# Check after resizing ("Avail" now shows 8.7G!-):
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/xvda1 16G 6.3G 8.7G 42% /
And by the way, there's no need to stop instance and detach EBS volume to resize it anymore! 13-Feb-2017 Amazon announced: "Amazon EBS Update -- New Elastic Volumes Change Everything" See my other SO answer for details.
Update: Use sudo xfs_growfs /dev/xvda1 instead of resize2fs when XFS filesystem