The SmartStor N4600 is a redesign of Promise's notoriously noisy NS4300N. The redesign includes a faster processor, more RAM and a properly-quiet fan.
The four bays support hot-swappable 3.5" SATA drives up to 2TB capacity in volume types of RAID 0,1,5, 5+ spare and 10. RAID expansion and migration are supported.
The N4600 exchanges the Freescale MPC8343 and 128 MB of RAM used in the NS4300N for a 600 MHz Intel EP80579 and 256 MB of soldered-on-board memory that provides a nice performance boost. Other key components include 128 MB of flash, Promise PDC42819 SATA controller and an IC+ IP1001 providing the single Gigabit Ethernet port that supports jumbo frames up to 16000 Bytes. Drives are formatted using a modified EXT3 filesystem that is not readable by most open source distros.
Two USB 2.0 ports and a single eSATA port can be used to attach external drives for storage expansion and print serving (USB only).
Power consumption measured 55 W with four Seagate ST3250623NS NL35 250 GB drives, provided by Promise, installed. NS4300N owners may be happy (or frustrated) to know that fan and drive noise are low, meaning the NAS is slightly audible in a quiet room, even under the sustained load of our performance testing.
Drives can be spun down to save power after a programmable interval between 3 minutes and 5 hours, which reduces consumption to 25 W. Wake on LAN can also be enabled, but shutdown / startup schedules are not provided.
CIFS/SMB, AFP and NFS network file systems are supported, and files can also be accessed via FTP and secure FTP. HTTPS is not supported for admin access. There is also no iSCSI or DFS support for building simple SANs.
Media features include iTunes and UPnP AV / DLNA servers and there is a simple web interface that supports browsing and downloading media files, viewing stored images and playing audio files in a web browser. I was able to get a Quicktime encoded (.mov) video to play in the browser. But attempting to play AVI and VOB files resulted in a download prompt. The "BT Server" plug-in downloads files via BitTorrent, HTTP, FTP and eDonkey servers.
Backup features include volume snapshots stored to disk and schedulable whole-volume replication to another networked server. There is also the ability to push-button trigger backups from Windows clients running a bundled backup utility. But there is no way to backup NAS shares to attached drives or to select individual folders for NAS-to-NAS backup.
Performance is significantly improved from that of the NS4300N and is competitive with other current-generation four-bay RAID 5 NASes. RAID 5 write performance with a Gigabit LAN connection averaged 55.1 MB/s for file sizes between 32 MB and 4 GB, with cached behavior not included in the average calculation. Read performance was lower, however, measuring 41.7 MB/s with the same conditions. File copy results varied significantly from the iozone method results. Using a Vista SP1 client under the same conditions (RAID 1, Gigabit LAN) produced 28.8 MB/s for write and 61.9 MB/s for read.