Problems extending a disk in Red Hat Enterprise Linux 7.3

Following one of my much earlier posts: -

 Increasing the size of a partition using Red Hat Enterprise Linux 6.3

I hit a bit of a snag.

This all worked: -

fdisk /dev/sda         -    to add a new partition ( having extended the disk using VMware Workstation )

reboot

pvcreate /dev/sda3

  Physical volume "/dev/sda3" successfully created.

vgextend rhel /dev/sda3

  Volume group "rhel" successfully extended

lvextend /dev/rhel/root /dev/sda3

  Size of logical volume rhel/root changed from 47.46 GiB (12151 extents) to 97.46 GiB (24950 extents).
  Logical volume rhel/root successfully resized.

but this step failed: -

resize2fs -p /dev/rhel/root

resize2fs 1.42.9 (28-Dec-2013)
resize2fs: Bad magic number in super-block while trying to open /dev/rhel/root
Couldn't find valid filesystem superblock.

As ever, the internet had the answer: -

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

After a bit of trial and error... as mentioned in the possible answers, it turned out to require xfs_growfs rather than resize2fs.

So I tried xfs_grow instead: -

xfs_growfs /dev/rhel/root

meta-data=/dev/mapper/rhel-root  isize=256    agcount=4, agsize=3110656 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=12442624, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal               bsize=4096   blocks=6075, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 12442624 to 25548800

and now my disk is twice the original size: -

 df -kmh

Filesystem             Size  Used Avail Use% Mounted on
/dev/mapper/rhel-root   98G  9.2G   89G  10% /
devtmpfs               4.8G     0  4.8G   0% /dev
tmpfs                  4.8G     0  4.8G   0% /dev/shm
tmpfs                  4.8G  8.6M  4.8G   1% /run
tmpfs                  4.8G     0  4.8G   0% /sys/fs/cgroup
/dev/sda1              497M  219M  278M  45% /boot
tmpfs                  983M     0  983M   0% /run/user/0

which is awesome.