Ext3 is an improved and compatible version of the Ext2 filesystem for Linux. It was introduced in kernel 2.2 and 2.4 (back in 1999).
Contents
Features
Journaling (see ext3.txt in the See Also section)
Extended User Attributes (needs to be enabled at mount time, see user_xattr in mount(8). See also lsattr(1)).
Access Control Lists, POSIX conformant. (needs to be enabled at mount time, see acl in mount(8). See also getfacl(1) from acl).
Quotas. (needs to be enabled at mount time, see quota in mount(8). See also edquota(1) from quota).
Compatibility
Ext3 was the default filesystem in Debian between Potato or Woody, and Debian 8 Jessie. It was superseded by ext4.
- It is possible to mount an ext3 file system using the ext2 driver (some features, like journaling won't be available).
- ext2/3 are extremely well supported by most tools (partitioning, resizing, bootloaders, etc...)
FAQ
- What are the default option for Ext3 partitions in Lenny?
ext_attr resize_inode dir_index filetype sparse_super large_file (See /etc/mke2fs.conf. Read the docs for the flags meaning)
- Can I resize an ext3 partition?
Yes. Either live (ext2online(8)) and/or offline (using ext2resize(8))
- Can I recover a deleted file?
Short answer: use your backup ! (otherwise try sometools like ext3grep)
- How to convert Ext3 to Ext4?
See http://ext4.wiki.kernel.org/index.php/Ext4_Howto (in squeeze or later)
- Can I read Ext3 partitions from Windows ?
Yes. Wikipedia Ext3 page list some tools.
Documentations
/usr/share/doc/linux-doc-2.6.XX/Documentation/filesystems/ext3.txt.gz, also available online for 2.6.29
Manpages: mkfs.ext3(8), mount(8), tune2fs(8).
See also
- Introductions:
KernelNewbies' Introduction to Ext3
http://kernelnewbies.org/Ext3
CategoryKernel | CategoryStorage | CategorySystemAdministration