- Highly scalable
- Instant cross-platform file sharing
- iSCSI target support
- Snapshot facility
- Integrated backup
- Optional data replication tools
- Hot-swap disk carriers can be fiddly
- Noisy fans
- RAID support implemented in firmware
Network Attached Storage (NAS) appliances are often relatively underpowered, low-capacity devices, designed to be used by small businesses, departmental workgroups and for branch office deployment. However, that’s not the case with the new Snap Server 650 from Adaptec which turns out to be a real beast of a machine capable of handling much larger workloads.
You can tell it’s special right from the start, with the new Snap Server housed in a large 1U rack-mount case with optional dual redundant power supplies and a far from quiet array of five cooling fans. Fortunately these are thermostatically controlled, but they’re still noisy even when the required temperature is obtained, making machine room deployment almost compulsory.
Open up the case and inside you find two 64-bit dual-core AMD Opteron processors. So what you’re getting is effectively a 4-way server with 2GB of memory as standard, expandable to 4GB in total using 553MHz ECC protected DIMMs.
Dual Gigabit Ethernet interfaces provide the necessary network connections, with port teaming support for both automatic failover and load balancing. The new Snap Server can also be configured as an iSCSI target to provide block-level SAN access as well as shared file storage.
The storage itself is connected via a Serial Attached SCSI (SAS) host bus adapter located in one of the server expansion slots; our review sample had four 300GB Seagate Cheetah 15,000rpm drives fitted. These drives slot into hot-swap bays behind a removable status panel that clips to the front of the unit, but could do with being easier to remove and replace (as could the somewhat fiddly mechanisms that locate the disks themselves).
Further expansion is achieved using optional Adaptec SANbloc S50 JBOD arrays, each of which can accommodate another 12 disks. Up to seven of these rack-mountable arrays can be attached to the Snap Server 650; when you do the maths, this gives it the potential to support an impressive 64.2TB of storage.
A Serial ATA (SATA) version of the Snap Server 650 is also due to be released soon, although this will be limited to a maximum capacity of 9TB.
There’s no hardware RAID support, but RAID is available in the firmware, and exactly how much of the storage will ultimately be available depends on how this gets configured. RAID 0 (disk striping), for example, allows the full capacity to be used, while RAID 1 (mirroring) gives much greater redundancy at the cost of halving the available storage.
The test server came with a default RAID 5 setup (disk striping with parity), which provides a high level of protection against individual drive failure while leaving a reasonable 843GB for file shares.
Global hot sparing is another option, as is Instant Capacity Expansion (ICE) whereby RAID volumes can be dynamically re-sized to take advantage of any new or larger disks, without having to shut down the array.
As with other Snap Servers, the 650 can act as a file server on a mix of Windows, Apple and Unix/Linux networks. However, instead of the Windows Server 2003 software employed on most other high-end NAS appliances, Adaptec employs its own Linux-based GuardianOS platform. Optimised for file sharing, this incorporates an XFS journaled file system and is managed either by a browser or, where several appliances are deployed, from a central Java-based console (Snap Server Manager).
Either way, the GuardianOS software is a lot easier to manage than trying to configure a general-purpose server, with lots of wizards to help with common tasks such as joining an Active Directory domain, managing shares and so on. Cross-platform file sharing is also enabled straight out of the box such that it took only a few minutes to get the Snap Server 650 working on our network and accessible from a mix of clients.
And it doesn’t stop there. As well as providing core file-sharing capabilities, GuardianOS also incorporates a number of data protection tools, including the ability to take instant snapshots of volumes to enable backups to be taken in real time without impacting performance or availability. Up to 256 snapshots can be stored with scheduling facilities also built in, although some data space needs to be sacrificed in order to support this option.
An integrated implementation of BakBone Software’s NetVault backup software is another standard feature, with support for a 500GB virtual tape library included in the price. Backups can also be taken to externally attached tape drives with agents for other backup software built in, along with a CA eTrust antivirus scanner with automatic updates.
Lastly, optional Snap EDR (Enterprise Data Replicator) software can be added to enable data held on a Snap Server to be replicated to another appliance. This adds a further £650 (ex. VAT) to the price, while for £1,300 (ex. VAT) you can perform one-to-many and many-to-one replications and also include Windows and Linux servers in the replication process.
As with storage capacity, performance is governed by the way the appliance is set up; for maximum throughput you’ll need a RAID 5 array and the Gigabit interfaces configured as a load balanced pair. Set up this way, the Snap Server 650 is more than a match for similarly specified Windows or Linux servers, which it can also match in terms of availability and beat hands-down when it comes to ease of setup and management.