Posts by Ching:

    How do you publish your NAS on the Internet?

    March 13th, 2014

    The first step to connecting to your NAS through the Internet is setting up a DDNS for your device.

    When users are setting up their NAS with the Intelligent NAS utility for the first time, they will be prompted to create their very own Thecus ID (or to log in with their ID if they already have one). But what exactly are the benefits of having a Thecus ID? One of the reasons to create a Thecus ID is that it gives the user access to the Thecus® free DDNS service. 

    Home network environment

    Because everyone’s home network is different, for the next few steps we have created a new guide.


    This document will guide you through checking your network environment and setting up your Thecus NAS to be accessible and configurable via the Internet. If you are unable to access services on your Thecus NAS via the Internet, this guide will also help you check your UPnP port forwarding settings. Examples of how to manually configure three different brands of router are also included.

    Please find the latest version of the guide here:


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    What is a Hot Spare?

    November 18th, 2013

    When one of the hard drives in a RAID group fails and an idle or standby drive immediately replaces the failed hard drive, this drive is known as a “hot spare”.

    The “hot spare” hard drive doesn’t store any data when it’s idle. It can be a global hot spare or a dedicated hot spare in a specific RAID group. When one of disks fails in a RAID group, the hot spare disk will replace the faulty one, and data will be rebuilt to the hot spare. This is only done via the data redundancy provided by other RAID disks, so RAID 0 cannot support hot spares. After finishing data rebuilding, a system administrator can take out the faulty disk, insert a new one, and assign it to be the new hot spare disk.

    Suggestions for hot spares:

    1. You have to check that the drive supports hot sparing.
    2. The capacity must larger or equal to the faulty drive.
    3. Use the same drives (brand, specifications, speed, etc.) if possible. For example, when you use 3 SAS 15000 RPM hard drives in a RAID 5, it’s better that the hot spare is SAS 15000 RPM, too. If you use a SATA III, it will slow down the entire RAID’s performance.

    RAID 5 + Hot Spare & RAID 6, which one is better


    RAID 5+Hot Spare: (N – 2) x (min. HDD capacity)

    You need at least four drives. Three are for RAID 5, and one acts as a hot spare. (Note: a RAID group can have one hot spare only.)

    RAID 6: (N – 2) x (min. HDD capacity)

    You need at least 4 drives. It offers 2 hard drive redundancy, with data striped across multiple disks along with a parity check bits. The parity check bits ensure data integrity.


    Both combinations share same number of drives and capacity, but RAID 6 offers a higher level data redundancy than RAID 5 and handles fault tolerance better, too. The overall data security for RAID 6 is better. The reason for this is that RAID 5 can only withstand one drive failure (with the hot spare drive ready to replace it). When there are two drive failures at the same time, the data cannot be saved. RAID 6, on the other hand, can withstand 2 drives failures at the same time. It does need time to rebuild data, however, on hot spare drive and this depends on the total capacity of the drives and the data’s size. There’s one con in regards to RAID 6: Because of the RAID 6’s additional fault tolerance mechanism, its performance is weaker than that of RAID 5.

    We usually use the same batch of drives, so once one of the drives fail, it’s possible that other drives are going to fail, too. Taking this into account, there’s the risk that on RAID5 systems with hot spares that another drive will fail while in the process of rebuilding data.


    Therefore, we should keep in mind that RAID data redundancy is not to the same as data backup. To ensure data safety, we need to back up our data daily to offline or off-site storage.

    Please refer to “Remote Backup“.

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    Thecus® N5550 Case Study by Syronex

    April 22nd, 2013

    Backup, local storage, sharing, antivirus and evolution needs now covered for Syronex.

    [slideshare id=19147649&doc=casestudyn5550syronex-130419054149-phpapp02]

    For more N5550 information, please go to:

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    Chinese Old Saying: A Wily Hare Has Three Burrows

    March 18th, 2013

    Introduction to Remote Backup

    Before introducing remote backup, we’ll go through some common terms associated with “backup” and find out the difference.

    Local Backup:

    “Local” means local device, it could possibly be a hard drive, desktop, and server or NAS that connects to an external device. In a sense, it’s like a DAS, external hard drive, external CD/DVD writer, tape drives, or other solid state storage, e.g. flash memory, thumb drive, CF card, SD cards by physical connection interfaces, for example, USB, eSATA, Optical, … to conduct unidirectional / bidirectional backup.

    Pros: faster speeds, and the user has full control over these devices to keep better privacy.

    Cons: external devices usually are at the same location with the local device, users have to do physical connection and backup files manually.

    Remote Backup:

    In short, it’s remote access through the internet to backup data on a local device (PC/NAS) to another.

    Pros:when encountering the worst case of natural or man-made disasters, there is a complete backup of the other end; another advantage is that you can set a scheduled backup, automatically or multi-machine.

    Cons: the data transfer speed will be affected by network bandwidth, and the setting is more complex than local backup, another issue is the higher cost.

    Additional, cloud backup of course is a kind of remote backup. However, cloud service does not lie in our own hands. Security issues are crucial.

    Remote Backup

    Now, we will introduce Thecus NAS-to-NAS remote backup solution.

    Why we suggest the method?

    At first, NAS, as the name implies “Network” is attached.

    Second, your data will be under dual-protection by RAID for data redundancy.


    The scenario below will show remote backup from a N5550 to N4800Eco.

    N5550: uses 5pcs 500GB SSD to build RAID5, there are iSCSI volume and shared folders, and multiple user access; we want to emphasize the performance and multiple user sharing.

    N4800Eco: 4pcs 4TB SATA III HDD to build RAID5, emphasize dual-protection by data redundancy.

    Scenario-Remote Backup: N5550 to N4800

    Ben is a MIS in an advertising design company which has about 30 people. It’s a miscellaneous work that everyday Ben has to maintain all kinds of devices, and back up all data that members generate. They purchased a Thecus N5550 to be a data pool inside the company. The N5550 makes Ben’s jobs easier and more convenient when he is in charge of network environment setting and data protection. So they bought a N4800Eco designed for data backup purposes.


    Ben’s Backup Plan: Scheduled Backup

    Each department saves their files to the N5550’s public folder. The backup plan Ben delivered is to do a full backup once a month. In the full backup setting, Ben chooses to compress files when he transfers because of the huge data.

    Full Backup: scheduled

    Request from Design Department: Real-time Backup Important Files

    The artwork (AD, film, …) created by designer is very important, it’s the product, the cash. If the products (digital files) that must be delivered to customers are damaged or gone, results in significant losses. Therefore custom backup fits the need. Ben selects the shared folder dedicated to Design department, backup type set to “Real-time.” Choose “Incremental” sync type to make the backup more efficiency because the file size is big and usually up to hundreds of megabytes. Ben only sets up once, and when designers add or revise files in the shared folder, the NAS will backup automatically.

    Custom backup

    Request from Administration Department: Document Archive

    Angela is responsible for arranging administration documents from each department. In addition to classifying them, those out of date but need to keep record have to be archived as well. Ben provides a backup plan for her. Because the backup is not an immediate task, Ben chooses the “Custom backup” option. He sets the backup type as “scheduled,” the N5550 will perform the backup task automatically once a week, and sync type is “incremental”.

    The data backup task is once and for all, and each task set does not take more than one minute to complete!

    Custom Backup: Document Archive


    Here’s the remote backup How-to guide:

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    Jumbo Frame

    January 14th, 2013

    What is giant frame / giant packetsJumbo Frame?

    Jumbo Frame is a feature that is supported on the NIC and hub; it’s specifically designed for Gigabit Ethernet industry standard, a long packet format. With Jumbo Frame, you can get Gigabit effectiveness of Ethernet network, allowing data transfer effectively of 50%-100%. A Jumbo Frame is anything bigger than 1518 bytes with a max of 9000 bytes and MPU default of 1500 bytes. In other words, the Jumbo Frame packet size is altered, in order to help processor cycles and bandwidth.

    Jumbo Frame is to modify packet size, to save number of transmitted packets.


    Recommended Jumbo Frame Timing

    • – Only applies to “large”, “long time” transmissions.
    • – Database backup
    • – HD Audio/Video streaming
    • – Video/Image Editing Environment

    Do not apply Jumbo Frame

    • – A network environment/small packet coexists or a small number of packets is large, Jumbo Frame will hinder performance.
    • – BT/eMule for this type of file transfer, do not apply Jumbo Frame because the source of non-fixed(IP/MAC)and data file has been altered to smaller files.


    Link Aggregation

    January 14th, 2013

    What is Link Aggregation

    Majority of Thecus® NAS offer seven modes of LAG (link aggregation). Load balance, Failover, 802.3ad, Balance-XOR, Balance-TLB, Broadcast and Balance-ALB.

    What is LAG?

    LAG is used to bond multiple links between your NAS and your switch into one bigger and faster link, increasing the network capacity while maintaining a fast transmission speed without changing any hardware devices, thus reducing cost. Doing so will offer optimal resource utilization, maximize throughput, minimize response time, and avoid overload. LAG also provides redundancy, fault tolerance or load balancing.

    Because every user has different needs and resources, many modes are available. Let’s have a closer look at the ones a Thecus® NAS can support.


    Why? When you don’t have a 10Gigabit network card, and frequently access more than 1Gigabit speeds for larger audio and video files, using Link Aggregation technology could expand network bandwidth. Thecus NAS provides Link Aggregation, and allows you to set Jumbo Frame (1500~9000 bytes) and aggregation type. The following describes the significance of these settings and supporting measures.




    Aggregation type:

    Load Balance: This LAG balances outgoing traffic across the active ports and accepts incoming traffic from any active port.

    When to use?

    • – The network service “constant line” demand can be used.
    • -When you have many small packets, you might also consider using, for example, when you use eMule/BT to download.
    • -MountNAS iSCSI LUN or a network drive to access video file editing work.
    • -When flow balance is required, cannot use Failover only.
    • -Different speed NIC can be shared, but not recommended.

    Failover: LAG in failover mode uses a main port for incoming and outgoing traffic between the two devices while the others are kept as backup. If the main fails, the other one immediately takes the charge. No special switch is required to support this. This mode provides fault tolerance.

    802.3ad: This mode requires a switch which can also support 802.3ad. This LAG mode uses the bandwidth of all available similar ports, sharing the transmission evenly.

    Balance-XOR: This mode dedicates one port for each destination address. XOR provides load balancing and fault tolerance.

    Broadcast: This mode uses all available ports to transmit the data towards the switch. If one port fails to transmit, the other ports assure the communication is completed, thus providing fault tolerance.

    Balance-TLB (Transmit Load Balance): This mode for packet sends and receives job-production of different mechanisms. For the send port with automatic load balancing and fault tolerance, and receive port only with fault-tolerant features, this mode does not switch to support and setting.

    Balance-ALB (Adaptive Load Balance): Send and receive at the same time with automatic load balancing and fault tolerance, when the failure of one network port, still operational sustainability; this mode does not switch to support and setting.

    How to set up the client-side system’s NIC?

    If you want to set up Jumbo Frame, you must first make sure that the network environment such as router / hub / switch specifications is supported. Even on the network, various client devices (PC/printer)have to support Jumbo Frame as well. For example, if a NAS set up to 9000 bytes Jumbo Frame, but the switch or PC does is not supported; this will cause packet restriction on receiving devices which are not supported, and will cause network bottlenecks at the router.

    We’ll describe Jumbo Frame in the next article.


    How Thecus NAS and Apple revolutionize your living room experience?

    December 25th, 2012

    How Thecus NAS and Apple revolutionize your living room experience?

    Recently, Apple CEO, Tim Cook, hint that Apple television will change the living room. “When I go into my living room and turn on the TV, I feel like I have gone backwards in time by 20 to 30 years,” Cook said during an interview on Rock Center with Brian Williams . “ It’s an area of intense interest. I can’t say more than that.” The collaboration between HongHai and Apple pushed out the new iTV, which stirs a consistent buzz on the internet. Before the advent of the iTV, let’s take a look at the Apple living room environment and the role that Thecus NAS plays.


    Your photos, home videos, music transferred from LP/CD are data and they are precious. Furthermore, movies, music albums, TV programs purchased from the iTunes store are all big data. A Macbook air has 500GB, iPad/iPhone/iPod provides up to 64GB. It seems you will need more storage capacity. Having your own personal storage device is very important. Thecus NAS supports iTunes server, DLNA, uPnP, and not only does it offer a huge amount of storage space but also provides full network capabilities. Assuming two 1TB hard drives installed in the N2800 with JBOD equals 2TB.

    2TB = 2000GB = 426,000 songs = 500 movies = 800,000 photos

    Songs: A 4 minute 128-Kbps AAC, transcoding input from the CD, each song is about 4.7MB

    Movies: 120 minutes of 720p HD (download from iTunes store), each about 4GB

    Photos: with 3264×2448 pixels JPEG (iPhone camera shooting) average of each is approximately 2.5MB

    If you think that’s not enough, you may install two 4TB hard drives with JBOD, with a gain of 8TB capacity or two 4TB hard drives with RAID 1; the volume you get is 4TB with data mirroring protection.


    How NAS helps Video Editor/Visual Designer/3D SOHO Part I: Time is Money

    December 21st, 2012

    Many SOHO or small studios specialize in video post-production, 3D animation or visual designers; there will be computer/workstation performance issues, as well storage capacity issues. Regarding, audio and video files, recording high definition video of the original file is in itself, a huge amount of data. For a 1.5 min, 30-frame per second 1080p video consists of more than 100 MB. In a project to produce special effects; requires a number of simultaneous processing of the original file, editing video files is even larger.

    Regardless of creative thinking aspects and the value of the SOHO / small studios, animation or video post-production are denominated by seconds to maintain revenues in a case worker; computer efficiency affects the number of hours of work while working on a project. The computer’s basic requirements are nothing more than a, CPU, memory, hard disk speed, and hard disk capacity.

    WorkerSoftware(operating system recommended 64bit)Primarily to enhance hardware
    Photo/VideoAdobe PhotoshopMemery、RAM Disk、Hard drive buffer
    Drawing ProcessAdobe Illustrator, Adobe IndesignProfessional graphics card, memory & virtual buffer memory
    Video post-productionAdobe Premiere, Adobe After Effect, Final cutProfessional graphics cards, hard drives array, 1080p video editing emphasize on hard disk access speed-oriented efficiency
    3DAutodeskProfessional graphics card (OpenGL), CPU(multi-core), memory

    Operating systems (recommendation 64bit) affect effectiveness and stability. Graphics card affects 3D real-time preview and rendering speed, CPU affects 2D/3D vector graphics drawing speed, memory effect bitmap image processing, and the speed of data access depends on hard drive speed and RAID type. In addition, software and content editing process will generate temporary files which are usually large and occupy the temporary disk space before you saving them.Personal or small studios may not be an investment of a workstation because the cost is too high. This article will focus on how NAS can help individuals or small studio workers to improve work efficiency at relatively low cost and storage issues. Software aspects in this article will be familiar to most producer/designers for example, Adobe series.

    Work ProcessHardware Resource
    Vector WireframeCPU
    3D Real-time Review/RenderGPU
    Working LayerRAM
    Bitmap EffectRAM
    Temporary filesRAM, Hard disk Cache
    Video encoding/decodingCPU

    The Adobe’s official product help, referred to the following principles:Regardless of Photoshop, Illustrator, After Effect or Premiere; Adobe Photoshop “performance” setting in “preference” item, which you can specify “scratch disk”, if originally there are several disks in your working computer, or single hard disk into several different logical partitions, then it can be assigned to a disk to share. However, if it is only one system disk (C drive), it could face a predicament and cannot be expanded. Refill it? We have a more flexible approach.

    The following guidelines can help you assign scratch disks:

    • For best performance, scratch disks should be on a different drive than any large files you are editing.
    • Scratch disks should be on a different drive than the one your operating system uses for virtual memory.
    • RAID disks/disk arrays are good choices for dedicated scratch disk volumes.
    • Drives with scratch disks should be defragmented regularly.


    Thecus NAS fulfills your needs, different types of RAID, or even multiple RAID for data protection and access speed. However, another focus of this article is to take advantage of the iSCSI allocation. Due to the iSCSI Target as a LUN, that is, when the client specifies the host to it (such as Windows iSCSI initiator), it is a logical disk, and you can specify it as “scratch disk”. Because it is an array disk, enhanced performance increases significantly. But don’t forget the speed of the network environment is a key point, especially when you are installing a 10G adapter; not to worry. If not on 10GbE network environment, most Thecus devices are equipped with Dual LAN ports; and Link Aggregation can be implemented to improve network speed. Thecus NAS technology for expanded storage space, support Stacking or Volume Expansion (depending on model). Thecus provides several different types of volume expansion solutions for the greatest flexibility.



    The Differences between block-level and file-level

    December 6th, 2012

    The Differences between block-level and file-level


    Digital Living with HDMI & DLNA

    October 11th, 2012

    Digital Living with DLNA and HDMI