resize2fs: Bad magic number in super-block while trying to open

The OP stated that he was using the XFS filesystem. The tool resize2fs works with ext2, ext3 and ext4 only.

There’s a similar tool available for the XFS filesytem called xfs_growfs. You’ll most likely have to install it first

sudo yum install xfsprogs.x86_64 --assumeyes

then mount your filesystem

sudo mount -t xfs /dev/sdf /vol

now you can extend the filesystem

sudo xfs_growfs /vol

df -h should now show more available space

I hope this helped 🙂

Tip: ext4 filesystem is the recommended filesystem for EBS volumes ( for the future )