Since the Linux OS will be the most compatible option for reading such a drive format, the first methods include simply installing Linux and using it as the filesystem management interface: There are several approaches that can be taken to manage Ext2 and Ext3 filesystems in OS X. In addition to those who might wish to dual boot OS X with Linux and manage files in both environments, there are those who might simply have an Ext2- or Ext3-formatted external drive that they need to read on their OS X systems. Apple discussion poster " rcb4" asks: "I was wondering since I want to dual boot Linux and OS X, putting each respective OS on their own smaller partition and creating a large /home partition for all my data" While Apple's cross-platform support is provided primarily for compatibility with Windows systems, there are instances when people may wish to use Linux disks with their Mac systems. While this support does allow a decent amount of flexibility in what disks can be handled by OS X, it does leave out support for some popular alternatives such as the ext2 and ext3 formats used in Linux.
However, to increase cross-platform support Apple has included support for several other filesystem types, including FAT32, UDF, UFS, and NTFS (in read only mode), in addition to several networking filesystem protocols such as AFP, NFS, and SMB.
MAC OS EXT4 SUPPORT MAC OS X
The primary filesystem format in OS X is Apple's HFS Plus (or Mac OS X Extended), which is the default used for any newly formatted disk.