Btrfs is under development as a file system capable of addressing and managing more files, larger files, and larger volumes than the ext2, ext3, and ext4 file systems. Btrfs is designed to make the file system tolerant of errors, and to facilitate the detection and repair of errors when they do occur. It uses checksums to ensure the validity of data and metadata, and maintains snapshots of the file system that can be used for backup or repair.
This filesystem snapshot feature is available in Fedora for the first time in Fedora 13. An automatic snapshot is created every time that the yum package manager performs an installation or upgrade.
Because Btrfs is still experimental and under development, the installation program does not offer it by default. If you want to create a Btrfs partition on a drive, you must commence the installation process with the boot option btrfs.
Passing the btrfs boot option on a DVD or CD based installation also allows Anaconda to access and mount a pre-existing btrfs partition. This option does not work with Fedora Live media.
Btrfs is still experimental
Fedora 13 includes Btrfs to allow you to experiment with this file system. You should not choose Btrfs for partitions that will contain valuable data or that are essential for the operation of important systems.
Fedora 13 now incorporates a number of improvements in NFS support.
Changes the default NFS protocol to version 4. NFSv4 will check to see if the server supports version 4. If the server does then it will connect. Otherwise it will connect using version 3.
One major benefit is performance. In version 4, the server has state which means it can communicate with each NFS client. This means the server can issue things called delegations (or leases) for files allowing the v4 client to aggressively cache, which drastically cuts down on network traffic between the client and server.
NFS Client IPv6 supports the mounting of NFS servers over IPv6. The benefits for Fedora users is that now servers and network file systems can talk to each other over IPv6 networks.
