I tried to resize my volume, but I got the error 'disk has unsupported feature(s): metadata_csum'

The version of e2fsprogs available for Ubuntu 16.04 doesn't work with disks or volumes that have the metadata_csum feature enabled. So, how do you fix it?

1. If you're working with a blockstorage volume, you can:

• Unmount and Detach the volume from your Ubuntu 16.04 Linode
• Create a new Linode in the same datacenter as your volume
• Deploy Debian 9 to the new Linode
• Attach your volume to the new Linode, and mount the volume
• Run your e2fsck and resize2fs commands
• Unmount and Detach the Volume
• Attach the volume to the original Ubuntu 16.04 Linode, and mount the volume.

2. Download and compile a new version of e2fsprogs
This is a little advanced, so proceed at your own risk.

First, logged in as root, let's create a directory to work with:

$ mkdir -p /src/e2fsprogs
$ cd /src/e2fsprogs

Next, we need to download a new version of e2fsprogs from SourgeForge:

$ wget http://downloads.sourceforge.net/project/e2fsprogs/e2fsprogs/v1.43.1/e2fsprogs-1.43.1.tar.gz

Now, we can uncompress the tarball:

$ tar xzf e2fsprogs-1.43.1.tar.gz
$ cd e2fsprogs-1.43.1

Then, compile the new version:

$ ./configure
$ make
$ make install

This should replace the versions of e2fsck and resize2fs automatically, but if you have trouble running these commands, try running

$ whereis resize2fs
$ whereis e2fsck

This will return something like this (which will tell you where e2fsck is -- there could be multiple versions installed):

$ whereis e2fsck
e2fsck: /sbin/e2fsck

You can run it directly and verify that it's the new version:

$ /sbin/e2fsck -V
e2fsck 1.43.4 (31-Jan-2017)
Using EXT2FS Library version 1.43.4, 31-Jan-2017