It's hard for many IT managers to even consider using open source software to handle anything remotely critical to running the business. That especially applies to storing company files in a reliable and manageable fashion.
But choosing open source as a platform does offer some help in solving both budget and user needs. In the case of NAS solutions, you get to pick what hardware to use, and you have lots of options when it comes to customization.
The two options under consideration in this article are FreeNAS and OpenFiler. Both have been around for a while and have many of the features you would expect in a business-class storage system. While FreeNAS is completely open source, OpenFiler has taken the approach of offering a base system for free but charging a fee for some additional features. You can still put together a usable system with the free version, but you might want to consider some of the paid options for the improvements they offer.
There are a number of other open source NAS solutions out there, but these two seemed to have the most active development and most enthusiastic user base.
To test the two distributions, we used a system based on an AMD Phenom II X6 1090T processor and an ASUS M4A89GTD PRO/USB3 motherboard, which has support for up to four 6 Gb/s SATA disks. For the system disk, we were provided with two of the new Seagate 500 GB SSHD hybrid drives and used one for each installation. We used Seagate Barracuda 2 TB drives for the data disks. For the benchmarks, we used a single data drive for testing both distributions in order to compare the same hardware.
FreeNAS is definitely the easier of the two to get up and running. After downloading the latest distribution (8.3.0) and burning the .iso file to a CD, it takes only another ten to fifteen minutes from start to finish to have a working system up and running. Most of the default options are reasonable and get you started quickly using the system. The documentation does recommend doing things like changing the default administrator password before you do anything else.
OpenFiler (version 2.99) was a bit more of a challenge to get to the same usable state as FreeNAS. One tip here is to make sure you start with clean disks as OpenFiler doesn't take too well to existing file systems. The documentation on the OpenFiler website is a bit sparse, but we found several good tutorials available on the Web. A quick search for installing OpenFiler on Youtube brings up a number of videos.
To configure OpenFiler, you must have some type of user authentication enabled. This can be a local instance of LDAP, which is provided but not enabled or configured. You must complete this step and then establish a group prior to creating your first user. Once you have a group created, you will be able to create users to put into that group. Creating a shared volume requires about the same number of steps. In the final step, you must create a shared folder and then enable it, as it is set to disabled by default. You must also enable CIFS before you'll be able to share files over a Windows network.
Both FreeNAS and OpenFiler use a Web-based management interface to control all aspects of the file server. FreeNas comes much more ready-to-run, so you might not have a need to walk through as much of the interface as you would with OpenFiler. From a user interaction perspective, it seems easier to accomplish the different tasks in the FreeNAS Web interface. It also seems much snappier than the OpenFiler interface. FreeNAS has a nice graphical system status screen (Figure 1) showing everything from disk performance and percentage usage to network bandwidth.
Figure 1. FreeNAS System Status Screen
There is an argument from a security perspective of "default nothing" for any setting that might open up an insecure path to your storage system. In this light, OpenFiler shines bright as it takes this approach to the extreme. Figure 2 shows the Network host access screen where everything is initially set to No for access. You have to manually change these settings on any new share to allow access. The Web management interface does make it possible to do everything necessary to keep the NAS running, including opening up an SSH terminal to the system.
Figure 2. OpenFiler Network Host Access Screen
Figures 3 and 4 show the output of the Crystal Diskmark tool connecting to a shared drive for FreeNAS and OpenFiler, respectively. Figures 5 (FreeNAS) and 6 (OpenFiler) show the iSCSI performance. While OpenFiler was behind FreeNAS in the setup and management categories, it came out ahead in the performance test. Both the iSCSI and SMB file shares showed higher throughput numbers for OpenFiler.
Figure 3. Crystal Diskmark Results for FreeNAS (Shared Drive)
Figure 4. Crystal Diskmark Results for OpenFiler (Shared Drive)
Figure 5. FreeNAS iSCI Performance
Figure 6. OpenFiler iSCI Performance
FreeNAS allows you to attach an entire physical device to an iSCSI target, which should increase the overall performance you can get. One of the commercial offerings from the OpenFiler group is an iSCSI plugin that is supposed to deliver even higher numbers. We did not obtain this plugin as the goal was to compare the two distributions based on freely available software.
From a management and ease-of-use perspective, the FreeNAS distribution definitely stands out over OpenFiler. Both projects are in active development with new releases coming out at regular intervals. This should provide an extra level of comfort to any IT manager looking at the possibility of going with an open source solution for storage. Both offerings provide a wealth of options and should work well once you get them up and running.