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ext2 (second extended filesystem) is an open source disk filesystem created for Linux.



Activate the following kernel options for ext2 support:

KERNEL Enabling ext2 support
File systems  --->
   <*> Second extended fs support

Support for optional ext2 features:

KERNEL Enabling ext2
File systems  --->
   [*]   Ext2 extended attributes
   [*]     Ext2 POSIX Access Control Lists
   [*]     Ext2 Security Labels
Optional ext2 support definitions
Option Description
Ext2 extended attributes Extended attributes are name:value pairs associated with inodes by the kernel or by users. See http://acl.bestbits.at/
Ext2 POSIX Access Control Lists Posix Access Control Lists (ACLs) support permissions for users and groups beyond the owner/group/world scheme. See http://acl.bestbits.at/
Ext2 Security Labels Enables an extended attribute handler for file security.

Large drive support

When the system has large disks (2 TB or greater) and a 32-bit (x86) kernel is being used, the following option (CONFIG_LBDAF) must be enabled:

KERNEL Enabling large drives for x86 kernels
-*- Enable the block layer  --->
    [*]   Support for large (2TB+) block devices and files

USE flags

The sys-fs/e2fsprogs package contains the utilities to work with the filesystem. In Gentoo Linux sys-fs/e2fsprogs is part of the system set and should be already installed on the system.

USE flags for sys-fs/e2fsprogs Standard EXT2/EXT3/EXT4 filesystem utilities

fuse Build fuse2fs, a FUSE file system client for ext2/ext3/ext4 file systems
static-libs Build static versions of dynamic libraries as well


After setting the USE flag update the system so the changes take effect:

root #emerge --ask --changed-use --deep @world



The mkfs.ext2 command irreversibly destroys any content of the partition it is told to format. Be sure to select the right partition!

To create an ext2 filesystem on the /dev/sda1 partition:

root #mkfs.ext2 /dev/sda1

Please replace /dev/sda1 with the actual partition to format.

By default, 5% of available disk space is reserved for the root user. This is usually a good thing for the partition where the / directory is mounted, but it may be not desirable on other partitions. To lose reserve disk space for the root user use mkfs.ext2's -m 0 option:

root #mkfs.ext2 -m 0 /dev/sda1