Recently we installed another server with a 24TB raid 5 set that needed to be mounted on a specific directory allowing access to all the avaliable disk space in the one directory.

Anaconda, right up to RHEL 6.5 has an issue with formatting partitions greater than 16TB and is caused by the partition size being expressed as a 32bit integer. This is a known limitation of most ext4 tools even in RHEL6 being 32bit tools.

There are two ways to resolve this issue. One is to move to xfs, the new default for RHEL 7, or you can upgrade the e2fsprogs to a version that is 64bit and supports upto 1EB, which is the original limit of ext4.

Moving to xfs has the added benefit of the new theoretical limit of 18EB as defined on http://xfs.org/.

XFS has been supportable in Red Hat Enterprise Linux since RHEL 6.5 by default without the need for an additional subscription through the Red Hat Network. Pre RHEL 6.5, an additional subscription was required.

As I use kickstart files for all installations it was a matter of two small modifications.

logvol /data --fstype=ext4 --name=data --vgname=store --size=1000 --grow

changed to

logvol /data --fstype=xfs --name=data --vgname=store --size=1000 --grow

And I needed to add xfsprogs to the installed packages to ensure that xfs partitions were supportable after the installation.

After the installation completed and system booted a quick check of the partitions showed that a 23TB partition had been created and mounted.

/dev/mapper/data-store     23T    45M    23T    1% /data