What are the file and file system size limitations for Red Hat Enterprise Linux?

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux
  • Optional: Global File System version 2 (GFS2) (requires Red Hat Cluster Suite, not supported on a single server)
  • Optional: XFS
  • File system limitation

Issue

  • What are the file and file system size limitations for Red Hat Enterprise Linux?
  • Are GFS2 file systems over 25 TB supported?
  • Is it possible to use Ext3 for file systems 16TB and above on Red Hat Enterprise Linux?
  • I cannot create a 20TB file system in Ext4 or Ext3.
  • Is it possible to use Ext3 for a very large file system (16 TB and above)? If not, which file system is recommended for very large file systems?
  • What is the maximum file size supported within a file system?

Resolution

This following information can be found in the File systems and storage limits section in our Red Hat Enterprise Linux versions comparison chart: Red Hat Enterprise Linux technology capabilities and limits .

Certified and [maximum] individual file size

File system RHEL 3 RHEL 4 RHEL 5 RHEL 6 RHEL 7 RHEL 8
Ext2/3 1TiB (3.0) 2TiB (3.5+) 2TiB 2TiB 2TiB 2TiB 2TiB
Ext4 n/a n/a 16TiB (5.6+)2 16TiB 16TiB 16TiB
GFS1 2TiB 16TiB [8EiB] 16TiB [8EiB] n/a n/a n/a
GFS21 n/a n/a 100TiB (5.3+) [8EiB] 100TiB [8EiB] 100TiB [8EiB] 100TiB [8EiB]
XFS3 n/a n/a 100TiB [8EiB] 100TiB [8EiB] 500TiB [8EiB] 8EiB

Certified and [maximum] file system size

File system RHEL 3 RHEL 4 RHEL 5 RHEL 6 RHEL 7 RHEL 8
Ext2/3 1TiB (3.0) 2TiB (3.5+) [8TiB] 8TiB 8TiB (5.0), 16TiB (5.1+)4 16TiB 16TiB 16TiB
Ext4 n/a n/a 16TiB [1EiB] (5.6+)2 16TiB [1EiB] 50TiB [1EiB] 50TiB [1EiB]
GFS 2TiB 16TiB [8EiB] 16TiB [8EiB] n/a n/a n/a
GFS21 n/a n/a 100TiB (5.3+) [8EiB] 100TiB [8EiB] 100TiB [8EiB] 100TiB [8EiB]
XFS3 n/a n/a 100TiB [16EiB] 300TiB [16EiB]5 500TiB [16EiB] 1PiB

Units

Units are given in binary prefix:

  • TiB = Tebibyte = 240
  • PiB = Pebibyte = 250
  • EiB = Exbibyte = 260

Theoretical limits

The difference between certified and maximum limit is that certified indicates what the file system has been tested to versus what the theoretical maximums are within the code base.

For example, GFS2 is a 64-bit based file system and has a theoretical limit of 8EiB, but only file systems up to the size in the above table have actually been tested so that is what is certified.

Red Hat will investigate, troubleshoot, and file bugs as needed on larger file systems. Engineering will make a commercially reasonable effort to fix bugs stemming from usage of file systems above supported limits. We may rely on customers for testing of patches and confirmation of fixes before rolling them into an official errata. If we cannot test patches which may provide solutions to issues, possible release of related fixes will be delayed.

Notes

  1. The GFS2 file system is based on a 64-bit architecture, which can theoretically accommodate an 8 EiB file system. However, the current supported maximum size of a GFS2 file system is 100 TiB. Though we can create large file systems on GFS2, in Red Hat Enterprise Linux 5.4, the use of GFS2 as a single server file system (i.e. not in a clustered environment) is deprecated. For details, see https://access.redhat.com/articles/5892.

  2. The Ext4 file system was a Technology Preview in RHEL 5.3, 5.4, and 5.5. RHEL 5.6 introduced full support for Ext4 as documented in the Release Notes.

  3. The solution for large file systems is to use XFS. The XFS file system is specifically targeted at very large file systems (16 TiB and above). Before RHEL 7, XFS userland was not be available in the base RHEL channel on RHN, it was provided as a layered product. Although GFS also supports very large file systems, its use is limited to Red Hat Cluster Suite environments. The maximum offset for sparse files of XFS is 8 EiB.

  4. The maximum capacity of the Ext3 is currently 16TiB. This enhancement was originally included in Red Hat Enterprise Linux 5 as a Technology Preview, and fully supported from RHEL 5.1 onward. Prior to this change, the maximum capacity available in RHEL 5.0 was 8TiB.

  5. Red Hat Enterprise Linux 6.8 or newer is required for 300TiB XFS file system support on RHEL 6.x. The previous maximum supported XFS file system size in RHEL 6.7 and earlier was 100TiB.

  • RHEL 5.1 Release Notes

  • To create an Ext3 file system larger than 8 TiB, you might need to use the mkfs.ext3 utility with 4K blocks and the -F option:

    # mkfs.ext3 -F -b 4096 /dev/BiggerGroup/biggervol

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