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Troubleshoot - by Hostrare

Update On: 23 Jul 2021Linux ext2, ext3 and ext4 file systems

When you install CentOS, cPanel suggests using an ext filesystem ext2, ext3, or ext4. If you are applying CentOS 5.x with the ext4 filesystem, you will require to download and install the package mentioned in the Red Hat documentation.
When you install Red Hat Enterprise Linux (RHEL), cPanel suggests that you use an ext filesystem (ext2, ext3, or ext4). If you use Red Hat 5.x with the ext4 filesystem, you will want to download and install the package specified in the Red Hat documentatio

Ext2 File System

Ext2 stands for the second lengthened file system.

It was organized in 1993. Developed by Rémy Card.

This was developed to overcome the limitation of the original ext file system.

Ext2 does not have a journaling feature.

On flash drives, USB drives, ext2 is recommended, as it doesn’t require doing the overhead of journaling.

Maximum specific file size can be from 16 GB to 2 TB

Overall ext2 file method size can be from 2 TB to 32 TB

Ext3 File System

Ext3 holds for the third extended file system.

It was founded in 2001. Developed by Stephen Tweedie.

Beginning from Linux Kernel 2.4.15 ext3 was available.

The main profit of ext3 is that it allows journaling.

Journaling has a dedicated space in the file method, where all the differences are tracked. This allows it to be more robust in checking file corruption, particularly when write methods are interrupted suddenly.

Maximum specific file size can be from 16 GB to 2 TB

Overall ext3 file system size can be from 2 TB to 32 TB

The ext3 filesystem provides three options.

These are as follows:

writeback – the greater speed at the price of bounded data sincerity. Allows old data to show up in files after a crash and relies on kernel’s regular writebacks to flush fenders.

ordered – that the data is constant with the file system; recently-written files will never show up with garbage contents after a crash at the cost of some activity.

journal – Journals all data requiring greater journal space and reduced performance. The most secure data retention policy.

Ext4 File System

Ext4 holds for the fourth extended file system.

It was organized in 2008.

Starting from Linux Kernel 2.6.19 ext4 was free.

Supports huge specific file size and overall file system size.

Maximum individual file size can be from 16 GB to 16 TB

Overall maximum ext4 file system size is 1 EB (exabyte). 1 EB = 1024 PB (petabyte). 1 PB = 1024 TB (terabyte).

The directory can contain a maximum of 64,000 subdirectories (as opposed to 32,000 in ext3)

You can also mount an actual ext3 fs as ext4 fs (without having to upgrade it).

Several other new works are proposed in ext4: multiblock allocation, delayed allocation, journal checksum. fast fsck, etc. All you need to know is that these new features have improved the performance and reliability of the filesystem when matched to ext3.

In ext4, you also have the choice of turning the journaling feature “off”.

Please use this link to switch file systems from ext2 to ext3 or ext4.

http://www.thegeekstuff.com/2011/05/ext2-ext3-ext4/