Setting up FreeNAS
Flexible Storage
Whether you need a network storage solution for your enterprise or small business or a place to store your multimedia library, FreeNAS can help. It provides a powerful array of features that can be adapted to meet almost any storage needs.
Various aspects of FreeNAS [1] have been covered in previous issues of ADMIN magazine, including a look at version 9.1.1 in Issue 17 [2]. However, if you are new to FreeNAS and the general topic of Network-Attached Storage (NAS), this might be a good time to get to know FreeNAS from the ground up.
In this first of two articles about FreeNAS, I will accomplish the initial setup of a FreeNAS box. The next article will dive into integrating with Windows Active Directory, snapshots, replication, and backup. FreeNAS is a behemoth when it comes to features (see the "FreeNAS Features" box for details).
FreeNAS Features
- Runs on commodity 64-bit hardware
- Cross-platform file sharing support for Windows, OS X, Linux, and Unix, with support for CIFS, AFP, NFS, iSCSI, SSH, rsync, and FTP/TFTP protocols
- Virtualization support with XenServer and VMware
- Replication
- Multiple RAID types supported
- ZFS
- Data protection
- Many backup options
- Disk encryption
- Powerful web interface
- Easy and secure updates
- Plugins for third-party software, such as Bacula, BitTorrent Sync, ownCloud, Transmission, and others
- Commercial support from iXsystems
FreeNAS
Early versions of FreeNAS originate from the embedded firewall project m0n0wall, and the software has since undergone a complete metamorphosis. The current version is built on powerful open source technologies of FreeBSD, Python, and many others.
iXsystems
Many successful open source projects have some form of corporate backing. This provides a powerful financial base to help drive a project's development and support its existence. iXsystems [3] is the sponsor behind the FreeNAS project, but it doesn't end there. They, like most other open source companies, take it a step further by offering enhanced software, hardware, and support options. They offer a souped-up version of FreeNAS called TrueNAS for enterprise deployments. It differs in the options for performance enhancements, high-availability clustering, manageability improvements designed for large deployments, robust reporting, automated drive replacement, and others.
TrueNAS [4] is coupled with the company's own hardware and support. Hardware offerings are available from small home office systems to large enterprise storage solutions. These high-quality hardware options are great if you want a single point for support or don't care to engineer a storage solution yourself.
ZFS
One of the key powerful features of FreeNAS is the ZFS [5] filesystem originally created by Sun Microsystems, now Oracle Corporation. Note that ZFS combines the roles of both a filesystem and a volume manager. This revolutionary filesystem packs a powerful punch of features (see the "ZFS Features" box).
ZFS Features
- Massive Scalability – Up to 256 zebibytes
- Volume Management – ZFS is not just a powerful, feature-rich filesystem; it is also a suite of tools to manage your volumes/storage.
- Copy-on-write – When editing a file, original disk blocks are not altered. Allows versioning and rollback.
- Snapshots – Point-in-time read-only imaging of your data. This can be replicated to other systems.
- Storage Pools – Unlike traditional filesystems that must have a fixed-size disk geometry, you create pools with the disks you have and add your disks and create filesystems with the geometry and configuration you need from the pool.
- Continuous Integrity Checking – ZFS keeps a continuous checksum of the data. It does this by creating and verifying checksums as data is written to disk.
- Automatic Repair – If you've ever had to repair a RAID set with an inexpensive RAID card, you'll appreciate ZFS's automatic repair features.
- RAID – Many types of RAID are supported: Stripe, Mirror, RAIDZ.
- RAIDZ – This type of software RAID overcomes the write hole. No need for expensive RAID cards (although they are supported in JBOD (Just a Bunch of Disks) mode).
- Compression – Multiple types of compression are supported, such as: lzjb, gzip, zle.
Note that RAIDZ types are RAIDZ1, RAIDZ2, and RAIDZ3. The number (e.g., 1-3) represents the number of drives that can fail per virtual device without losing the pool. Parity is distributed across all disks. FreeNAS has the intelligence to pick the optimal configuration given the number of drives you have.
Additionally, the ZFS filesystem requires more overhead and therefore more RAM. A base of 8GB is recommended for this configuration. ZFS is a much better option if you meet the hardware requirements. My base configuration will have 16GB in this example, so I'll go with ZFS.
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