Built-on powerful Linux-embedded system with 500MHz SoC CPU and 512MB DDRII memory; it enables major business applications including storing, backing up, sharing and archiving critical information. TS-409U delivers enhanced reliability and expansibility; and offers powerful features including RAID 0/ 1/ 5/ 6/ 5+spare disk redundancy, Online RAID Capacity Expansion, Online RAID Level Migration, rock-solid hot-swap design, and abundant server functions. The HDD S.M.A.R.T. and complete log systems are supported to help IT administrators minimize the deployment cost and maintenance effort.

According to Mr. Troy Lin, product manager of QNAP, "TS-409U is positioned as the most affordable, reliable, and feature-rich 1U storage server to meet backup and storage demand. The best-in-class RAID on TS-409U brings users a higher level of data security; advanced RAID configurations such as RAID 6 and RAID 5 are supported. Moreover, TS-409U even allows one more hard drive failure than other NAS of the same level. In other words, users can rescue their critical data when 2 drives fail in RAID 5 or 3 drives fail in RAID 6. It effectively reduces the risk of data loss caused by failure of hard disks. With the value-plus all-in-one business server features, TS-409U is the ideal solution with best price performance ratio for growing SMB and enterprises."

TS-409U is also designed with unique expandability and upgradeability which meet business and IT challenges of fast growing business. With Online RAID Capacity Expansion, administrators can select to purchase the most cost-effective hard drives for initial server setup and upgrade to larger ones in the future. All the stored data will be kept and seamlessly moved to the newly installed hard drives without turning off the server. With Online RAID Level Migration, administrators can start from one drive firstly and add more drives to upgrade the RAID level in the future with the data retained.

TS-409U supports multiple file sharing protocols for users to share files across Linux, Unix, Mac, and Windows platforms. Abundant valuable server functions such as File Server, FTP Server, and Printer Server etc. are supported. Also, Windows AD (Active Directory) is supported to help create an easy-to-access environment and lower the maintenance cost. With the dual support of MySQL and SQLite, SMB & SOHO users can easily set up their own web and database servers. With the dual support of MySQL and SQLite, users can easily set up their own web and database servers. Moreover, users can make use of the encrypted remote replication and backup to external devices features for extra data protection. Various data storage and management mechanisms- FTP server with SSL/TLS encrypted technology, SSH login, and web page SSL login are also provided for secure data transfer and access.