My 2 Cents. MPC NAS Guide 2010



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My 2 Cents MPC NAS Guide 2010 hi-jack Isn t it exciting always, looking for that new thing to buy It always comes with a little scared feeling should you be looking for something you just don t understand completely understand yet, something you had no experience with before... There are so many flavors and questions surrounding products always Sure explanations always seem so simple, EZthis and EZthat It comes standard now indicating to users the whole product sets itself up at the push of a button These My 2Cents Guides are a push in the right direction to understand what comes with the product you are looking for, in this case, a NAS system might be on your agenda in the near future So let s run some basics and give you some advice w w w. m p c c l u b. c o m 3 / 1 1 / 2 0 1 0

Contents MPC NAS Guide 2010... 3 The basics in understanding NAS... 3 RAID... 3 About RAID... 3 2 Disks RAID0 or RAID1... 3 Conclusion RAID0 and RAID1... 4 RAID5: The most popular RAID configuration... 4 Conclusion RAID5... 5 RAID6:... 5 Conclusion RAID6... 6 Hot Spare... 6 BITMAP... 7 Pitfalls with NAS servers... 7 Low level users (1TB to 4TB)... 9 Medium level users (4TB up to 8TB)... 9 Advanced users (10+ TB)... 10 Let the fun begin: Choosing a NAS... 10 Features of a NAS... 11 Size matters... 11 NAS Convenience... 11 The Future of NAS for us Media Fans... 12 Concluding... 12

MPC NAS Guide 2010 Welcome to the first guide in our My2Cents series where we will discuss in detail how we feel you should approach selecting a NAS server for home use or at least, see how we would select such NAS if we were looking for one. Although it might seem an easy subject, it s not as the right choice depends on your needs, your ability to maintain a NAS or not technically, your environment has an influence (store it in the living room or the cellar?), you re family that may have to operate it, you may be limited in budget you can spend and so on As such, our My2Cents series take on a very simplistic approach to exclude all self build NAS servers or those that come without out of the box and ready to go experience. What we seek is decent, robust NAS with integrated media features that are easy to set up and require hardly any attention afterwards. The basics in understanding NAS It is wrong to believe a NAS is only for storing data on them and keep data reasonably safe. There s a lot more to a NAS nowadays than the thing it used to only do in the Ice Age. Nowadays NAS servers are not only data servers but also downloader s of data from the internet, showcasing your images, serving up media like movies and music to a plethora of media players, central backup storage and more... Proper usage of a NAS can bring a lot of convenience to you as owner. No skills are needed at all but a basic understanding of NAS is important. So before we start fiddling with the idea of selecting a NAS, let s run through some of the stuff you must know about NAS RAID RAID is the name of the configuration for a NAS when 2 or more hard drives are working together. There are different RAID configurations like RAID0, RAID1, RAID5 and RAID6 discussed in this guide. RAID is RAID! Whoever dares to speak those words is immediately banned into the lower region of knowledge. Raid comes in different flavors and each has its own pros and cons ranging from performance, safety and cost per GB which we use to calculate the best configuration vs. safety... Let's rack up them RAID's and see what the most common RAID configurations can do us for if deciding on Networked Storage. In this section, we explain what the most used raids are and what options come with them. About RAID RAID actually means Redundant Array of Independent Disks and refers mostly to combining disks in one volume with a level of redundancy that one or more disks may fail without loss of data. This is true for all cases, except for RAID0 which has no redundancy at all. We ll come back to that later NAS is mainly for sharing data on the network (that you know). There are different flavors ranging from a single disk system up to 8 disks in a system we know today from our preferred vendors being NetGear, Thecus, QNAP and Synology. Single disk systems can never be safe or redundant so any safety comes from backing up the data on an external disk. A single disk is also never RAID even though it's still called A NAS, correctly. NAS stands for Network Access Storage. Storage, you can access on the network. RAID comes into play if we talk about at least 2 hard drives. Dual disk systems start having RAID options (called RAID0 or RAID1) and multi disk systems with 3 drives and more are capable of more advanced RAID configurations (RAID5 and RAID6). For home users, we don t need to look further than these 4 RAID configurations so we limit ourselves to RAID0, RAID1, RAID5 and RAID6. 2 Disks RAID0 or RAID1 RAID0, also called STRIPE MODE, combines both disks into 1 single big volume and writes and reads from both disks at the same time (speed increases here so it s slightly more performant) but there is no safety whatsoever. If any of both drives fails, all data is lost, including the data from the drive which is still ok. This is because the data is written half on disk 1 and half on disk 2. A file is divided into blocks and both disks write parts of such file simultaneously on their disk The image illustrates a file that exists of 8 blocks, although 1 files, blocks are divided over both disks. This is the reason, if any disk breaks down, half the file data is gone and cannot be repaired. Either with single disk NAS or STRIPE mode, manual backups of your data to external storage are thus the only safety you can achieve here.

The other RAID option is RAID1, also called MIRROR MODE. This will automatically mirror all data from disk 1 upon disk 2 (exact copy) so if it fails, the other drive takes over and no data is lost. You can then replace the failing drive and the content is copied from disk 2 on disk 1, so we have a mirror mode again. This slows down the performance as every file has to be written twice. The image shows a file written of 4 blocks, all 4 blocks are written to both hard drives so you have an automatic backup. RAID5 requires at least 3 hard drives, preferably at least 4 (I explain later why). What happens here is that all drives will be combined into 1 big volume for storage but, the equivalent of 1 disk is lost to safety (parity). When writing data on a RAID5 configuration, parity of this data is kept on the other disks. Files written to disk 1 will have parity on disk 2 and/or disk 3, files written on disk 2 will have parity on disk 1 and/or disk 3 and you already guessed it, files written on disk 3 will have parity on disk 1 and/or disk 2. The following image shows RAID5 with 4 disks and its parity. Conclusion RAID0 and RAID1 Neither options sounds ideal, does it? In RAID0 you have maximum performance and storage capacity but no backup at all so up to 4TB data (2 X 2TB disk for instance) is at risk if anything goes wrong with either hard drive. In Mirror mode, we are safe with our data as we have a backup but we do waste a lot of storage space by mirroring the data. When using 2 X 2TB hard drives in a mirror, we have 2TB storage and 2TB backup. This is a costly solution for little storage space. The most affordable RAID possible is RAID0. Two hard drives in RAID0 mode would offer you 4TB volume as both are combined into one volume. Let s for argument s sake state a 2TB disk costs 150, the total cost per GB for 1 GB in this configuration would be 0.073 cents That s extremely cheap but do remember you have no safety at all This is not to be used for sensitive data you don t want to put at risk. RAID1, although costing the same 300 for two hard drives sized 2TB, is twice as expensive as one disk is used to mirror the other one so you actually write every file twice. This would cost you 0.14 cents per GB, twice as expensive as RAID0 but in this case, you do have a failsafe backup in case of one disk fails No data is lost. (Unless lightening strikes you and both drives are broken at the same time) RAID5: The most popular RAID configuration In case of RAID5, the matter becomes little more complex. Let s get rid of the wrong assumption some people have: RAID5 is limited to 5 disks. Wrong. The RAID5 name for this particular configuration has nothing to do with the amount of disks that can be used and it s just a name. Imagine, RAID0 is not based on 0 disks and RAID1 is not based on 1 disk but 2 etc just like RAID6 is not limited to 6 disks The above figure is an example of a RAID-5 layout using 4 disks. RAID-5 is an N+1 design which means you re actual storage disks (N) +1. This is a 3+1 layout, meaning that 3 disks worth of data are encoded onto 4 disks instead of 3, such that as long as 3 disks are available, the data remains accessible and can be recovered from the data (parity) on the other disks in the RAID5 by replacing the failed disk with a new one. Now why 4 drives or more? NAS storage is all about safety and sharing data with multiple clients (PC s, media players and so on ) so the assurance of uptime for your NAS is one of the important reasons people would invest in this type of storage. With 3 disks in RAID5, 1 disk is allowed to fail just the same as when using more drives and you will not have lost any data thanks to the parity stored on the other two disks. Your data however is not available if this should happen until the failing hard drive is replaced and the unit has rebuilt its RAID5 completely (6 24 hours). The process must be completed as RAID5 needs a minimum of 3 disks to operate.

With 4 disks however, even if a drive fails, your data remains available as a RAID5 can remain operational with minimal 3 disks in an array of 4, 4 disks in an array of 5 and 5 disks in an array of 6 hard drives and so on This is then called degraded mode. While your data remains available, you are not in a rush to replace the disk that failed but keep in mind, the longer you keep it in degraded mode, the more risk you take as if any other drive would fail now, your data would actually be lost. Let s emulate DISK 2 fails inside this configuration of a RAID5 with 4 disks and we replace it with a hard drive Disk 1, 3 and 4 contain parity from the second disk and will rebuild the data that was on it before, the part of the drive that contained parity before (Cp) will be regenerated as well. Hence this is the reason a second disk is not allowed to fail since part of the restoration info for the other drives is on the second disk that failed while the original disks contain their data. Losing a second disk would mean parity is lost and original data which then cannot be restored. Conclusion RAID5 RAID5 is likely the best option for home users in general. RAID also can give better performance than a single hard drive by splitting the data workload across the different disks. When choosing RAID5, a minimum of 4 hard drives is highly recommended. Never believe your data is 100% safe on any RAID configuration as errors can occur just like on normal hard drives. The only safety you have is the fact that one disk may break down which then means, nothing of your data is lost. Raid 5 is sensitive to bit errors when restoring took place since it has no data integrity checks integrated. Although no failure will be shown before accessing the actual file having a corrupt bit, it could mean occasional data is corrupted. This is a weakness in RAID5 and can happen in both non-degraded mode (fully operational), but especially in degraded mode which is sensitive to bit errors. Golden rule: Replace failing drives soonest possible! RAID6: RAID6 is very similar to RAID5 but in RAID6 there is a data integrity check involved that RAID5 is missing. Another difference here is that you need at least 4 or more hard drives to start a RAID6 configuration and in case of RAID6, 2 hard drives may break down without losing data. A RAID6 would use the equivalent of 2 hard drives for parity. Whenever a third disk fails, your RAID data is lost RAID5 or RAID in general is not a super safe option. It s not a backup either of your data. It s a system that offers reasonable insurance that if any drive fails, only 1 though, there is no data loss. When using 4 or more drives, always the equivalent of 1 disk is lost in space to parity so the more hard drives used in RAID5, the more affordable your price per GB becomes 3 Hard drives of 2TB: Costs per GB about 0.072 cents means 33% parity (1/3 rd ) 4 Hard drives of 2TB: Costs per GB about 0.065 cents means 25% parity (1/4th) 5 Hard drives of 2TB: Costs per GB about 0.061 cents means 20% parity (1/5th)

How the bit error rate correction works is rather simple There is the data hard drive containing the file, and two hard drives containing the parity of that file, resulting in three checks. In the event that one of the drives returns bad data, the other two can inform, they have a different bit with the 2 to 1 majority accepted as the correct data, allowing the system to detect and correct the error. Difficult explanation I know Let s say I have a file with the letter A in it and it becomes B. My file would say I m B whilst the two disks with parity would say, you are A 2 1 means the file is corrected to state it s A I don t know how to explain it differently Cost per GB on a RAID6 configuration with 6 drives starts at about 0.073 cents, the more drives you add again, the more affordable the cost per GB becomes. So let s emulate two drives failing then, shall we? Conclusion RAID6 Cost of RAID6 is higher than RAID5 since we lose 2 hard drives in such RAID for parity. Benefits are 2 hard drives may fail and we will not get any problems with bit error rates as the system can correct it. Changes on 1 bi error are already very small, 2 is almost unthinkable. RAID6 starts with a minimum of 4 hard drives (50% redundancy) and can have an undefined amount of disks (usually different based on support of the vendor, same as RAID5 by the way). As with RAID5, performance is better than a single drive considering again, the dividing of the work in read and write operations. Obviously, consumption of power is something to consider as well in all multi disk systems. Hot Spare Especially in remote locations NAS servers should be configured with a hot spare option, especially in RAID 5 (bit error rate and possible second disk failing). In RAID6, when 1 disk fails, it s less urgent due to the bit error rate correction system and the fact yet another disk is allowed to fail. All NAS usually come with email notification to report to the owner a disk has failed or some other error has occurred. In both RAID5 and RAID6 configurations, a HOT SPARE can therefore be a good solution buying you time. For example, I have a NAS that can hold 5 hard drives. My choice is to configure the RAID5 with all hard drives of 2TB maximizing the volume I will end up with. In a RAID5 configuration this would mean I end up with a storage volume of about 8TB and about 2TB of parity for safety so one disk is allowed to fail that I can replace. The parity stored on the failing disks is lost (Ap, Aq, Bq and Ep) and will be rebuilt by the system. The actual data that was on these disks is restored from the parity on the other three drives It s not so important to know how all this RAID stuff works in detail but it is nice to know the differences, the pros and the cons, information you need whenever deciding how safe you want your data to be. Choosing the right one is important. So that said we add one more option to discuss after the conclusion of RAID6 Let s imagine using a RAID5 configured with 5 disks and assign no hot spare disk. Any disk failing of the 5 in RAID5 has to be replaced soonest possible. If the NAS is stored in a remote location or you have no spare drive available, it may mean days before you get around to it. It can be prevented. This would mean we build a RAID5 using 4 hard drives of 2TB and assign the fifth as HOT Spare (requiring a 5-bay server). This fifth hard drive would then take the place automatically of the first disk that fails. Not only do I have a parity safety now but also an extra disk that kicks in as soon as any other fails without any data becoming unavailable to me when it would occur. This is at the cost of storage space though as in this configuration I end up with about 6TB of storage

space, 2TB used for parity and 2TB used as hot spare unlike the first example, I would have 8TB but no HOT SPARE feature. It s a give and take game of deciding how you want your NAS to be HOT SPARE is available on both RAID5 and RAID6. BITMAP We are really getting in deep now, but bare with us as also BITMAP is something a NAS owner should understand. In any RAID5 and RAID6 configuration, when a disk fails and the hot spare kicks in or a failing disk is replaced by a new one, the system will need to rebuild its RAID. This is a lengthy process that runs over hours of time depending on your volume size, up to 24 36 hours are not special. BITMAP is a function on some NAS models that allow this restore to happen within minutes (can help a lot in RAID5 with 3 disks to restore more quickly). It will be able to read from the other drives what data exactly was written on the drive that failed and restore only that drive to complete the rebuild instead of recalculating the full parity over all disks as would happen here normally when no BITMAP is used. BITMAP is tricky as it can consume little space but more severe depending on your NAS system of choice, can strongly influence the performance of read and write operations. You will have to check the impact of enabling BITMAP and then decide this feature is worth enabling for you or not. I usually do so during the first weeks and months of a new NAS being deployed, until I can trust its operations and compatibility with the hard drives of my choice. Pitfalls with NAS servers When using 3 disks of 2TB now, whenever you need to expand, you cannot use 2.5TB drives as the extra space would be lost (unless you replace the other drives one by one as well with 2.5TB which is a very lengthy process). The maximum amount of a hard drive used in a RAID configuration is the equivalent of the smallest disk in the array. That means, only 2TB will be used of the new drive instead of 2.5TB if you mix these Replacing hard drives one by one to eventually expand storage when all smaller hard drives are replaced, is a painful and lengthy process and in general not done. Therefore again, decide upon which hard drives to buy based on your needs for the coming 12 24 months. Then decide based on the amount of disks you need to achieve that storage, which unit fits your need, including possible HOT SPARE and your choice of configuration being RAID5 or RAID6 The investment starts from 200 including hard drive and can run up into thousands of. Know that a lot can be done for 1.000 Another important pitfall is to select your disks wisely. Not all hard drives will work properly in a NAS, some have reduced performance in NAS storage and so on. Most vendors provide a HDD compatibility list with their units they have tested or confirmed working. These lists are usually accessible from their main page. Watch the consumption of NAS as well, the size, the fans (noise levels) and so on Different Disk Size Solution are attractive It happens more often than we can imagine, people have gathered different hard drives over months and years and seek to put them to good use. Don t let features like Drobo presents them or Synology fool you of their inventions as they not always fit your needs It fits some combinations far better than others Possible to be done in RAID5 and RAID6 as explained before is using different sizes of hard drives but you will lose space this way and we do not recommend it. Remember, space on every disk will only be available up to the amount of space available on the smallest hard drive in such configurations. For instance, if we d make a RAID5 out of 3 disks sized 250GB and 1 sized 2TB, our volume would be 750GB + 250GB parity even though total capacity of disk space here is 2.75TB. Wouldn t it make more sense to just use the 2TB as storage then? Here s a funny outcome of using SHR on these 4 same disks, who will result in the same volume so you can easily see, doing this has no benefit at all unless you have similar sized disks and you can easily calculate what can be done with the disks you have Don t get us wrong, we do like this SHR system a lot but only under the right circumstances. You will still loose space but less using this system but do know it s only fit for bigger sized drives as the units are too expensive to fiddle with small disks in SHR mode and you will lose some performance up to 10 or 15%. Rather such SHR system is as safe and stable as a regular RAID is still something I wonder about So, we ll make things easy and will offer you firm example as to understand how the SHR would handle 5 different disks. With that, you will be able to see how it s built, what the pros and cons are and so on You will be able to calculate the outcome of any disks you have lying around to define whether SHR is something that could save you money and still deliver you with adequate resources of storage. Then you can decide, knowing how the system would build the volume, if it s not too much in the end Having 5 RAID s build is quite something to keep things together eventually and there s always risk with updates that might change a thing or two

Size Disk 1st RAID5 Synology SHR System 3rd RAID53 2nd RAID52 4th RAID1 Unused Space Available Storage 80GB 80GB X X X X 160GB 80GB 80GB X X X 250GB 80GB 80GB 90GB X X 320GB 80GB 80GB 90GB 70GB X 500GB 80GB 80GB 90GB 70GB 180GB Volume 320GB 240GB 180GB 70GB 810GB SHR would first build multiple raids and then combine these raids into one volume So, above is a table, easy to understand what would happen with the SHR system if we d purchased a DS1010+ from Synology as example to use our 5 older disks we have scattered around. We start off with 5 drives. Since we have more than 3 hard drives with space on them, SHR will create a RAID5 volume automatically and the rule applies that we start with the smallest size disk, in this case 80GB. SHR makes the 1 st RAID5 by taking 80GB from each disk to create the first volume. We now have a RAID5 with 320GB available storage + 80GB parity. We have leftover disk space now as follows: 80GB = 0GB as we used 80GB from it in the 1 st RAID5 160GB = 80GB as we used 80GB from it in the 1 st RAID5 250GB = 170GB as we used 80GB from it in the 1 st RAID5 320GB = 240GB as we used 80GB from it in the 1 st RAID5 500GB = 420GB as we used 80GB from it in the 1 st RAID5 Of these remaining 4 hard drives that still have space, SHR will create another RAID5 configuration based on the smallest capacity remaining, in this case, the disk of 160GB of which already 80GB is used. So it has left 80GB. SHR will again reserve 80GB from each drive leading to the second RAID5 configuration offering us 240GB available storage + 80GB parity. We have leftover disk space now as follows: 80GB = 0GB as we used 1 X 80GB from it in the 1 st RAID5 160GB = 0GB as we used 2 X 80GB from it in the 1 st and 2 nd RAID5 250GB = 90GB as we used 2 X 80GB from it in the 1 st and 2 nd RAID5 320GB = 160GB as we used 2 X 80GB from it in the 1 st and 2 nd RAID5 500GB = 340GB as we used 2 X 80GB from it in the 1 st and 2 nd RAID5 Now also the 160GB drive is used up completely and we have 3 disks that have space left so SHR will create another RAID5 only now the smallest capacity left on a hard drive is 90GB on the 250GB hard drive (250 80 80 = 90) so SHR will build a RAID5 using 3 X 90GB which leads to 180GB available storage + 90 GB parity. We have leftover disk space now as follows: 80GB = 0GB as we used 1 X 80GB from it in the 1 st RAID5 160GB = 0GB as we used 2 X 80GB from it in the 1 st and 2 nd RAID5 250GB = 0GB as we used 2 X 80GB + 1 X 90GB in the 1 st, 2 nd and 3 rd RAID5 320GB = 70GB as we used 2 X 80GB + 1 X 90GB in the 1 st, 2 nd and 3 rd RAID5 500GB = 250GB as we used 2 X 80GB + 1 X 90GB in the 1 st, 2 nd and 3 rd RAID5 Now we have only 2 disks left with space on them (70GB left of the 320GB hard drive is the smallest size still available) so we can no longer achieve a RAID5 configuration, as it needs minimum 3 disks. SHR will now fall back to creating a MIRROR (RAID1) leading to 70GB available storage which is mirrored on the other 70GB we took from the drive of 500GB. In the end, we wasted 180GB which is left from the 500GB hard drive which is a reasonable low amount but we have created a volume that is only 810GB in total size and build that volume over 3 RAID5 configurations and 1 RAID1 Mirror that somehow work together This doesn t feel too healthy to me at the cost of avoiding to buy 1TB hard drive ( 80) and a single disk NAS costing about 250 in total. Why invest in a system that can handle 5 hard drives (DS1010+ costs 750) to reach such poor end result because of SHR and using old disks? Secondly, what has most risk failing? 4 RAID configurations on top of each other susceptible to future FW updates or a single NAS with 1TB? Use you re brains peeps it s very important to make the right decisions in the long run as to when using SHR or regular solutions as the third questions is inevitable. How long do you think you d last with 810GB? While I m strongly for SHR system, they are only useful for bigger disks against the cost of such unit, you don t go buying expensive NAS to reach lower storage than a single hard drive, let alone building 4 raids to achieve less than 1TB.. Using any small disk in such setup immediately balances the cost of ownership way below zero compared to investing in any other solution Therefore, SHR is only useful if you have bigger sized disks lying around, don t fiddle with the small ones Seriously Buying a 750 costing unit to be able using old 250GB up to 750GB hard drives you have around is just not smart.

Low level users (1TB to 4TB) Low level users is what we aim for when stating people just need shared network storage for a low amount of data and are generally not collecting data but storing it, viewing it and then delete it again Changes are, they have enough with a single bay or dual bay NAS to do the job. Still, prices can run up high even though relatively small storage space is achieved. - Promise - Conceptronic - Raidsonic Usually there are several devices available to you with names like Pro behind them and Pro II. This is mainly indicating the unit has more memory, slightly more performance or some features people consider used by Pro s like Telnet and SSH. You can compare these units critically as price difference is often substantial between these units. If you only want to share data, the performance on the NAS is allowed to be less than optimal, you would only notice it if copying big chunks of data while streaming and sharing data will work just fine. If you intend to do a lot of copying back and forth, install applications that eat resources (like QueezeCenter) and so on, you have a reason to demand more performance and memory. So evaluate your needs to come to a good and funded decision and decide how safe your data must be to select MIRROR (safe) mode or STRIPE (unsafe). In fact, which RAID you want to use should be calculated in with the storage space you want to end up with. A single bay NAS with 1 2TB hard drive has the same capacity of useable storage against a DUAL bay system with 2 2TB hard drives in MIRROR mode (safe). The price difference can is big, even though you end up with 2TB storage space TIPS 1 Bay Regular (Fat recommended, Red Favorite): - QNAP TS-110, TS-119 - Synology DS110j, DS109, DS109+ TIPS 2 Bay Regular (Fat recommended): - NetGear DUO - QNAP TS-210, TS-219 / TS219p - Synology DS210j, DS209, DS209+, DS209+ II, DS-710+ - Thecus N2200 Other vendors to check when restricted on budget: Medium level users (4TB up to 8TB) Medium storage capacity is what most collectors would need who stick to storing the best only. Storing everything will cause you to run out of disk space quickly especially when storing DVD ISO and HD movies or even complete BluRays on NAS. Best option here would be selecting a NAS with 4 5 bays in a RAID5 configuration leading to 6TB or 8TB storage space when using 2TB or 4.5TB and 6TB using 1.5TB hard drives. Also here, devices exist in different flavors so depending on your needs and skills, select the one that is most close to you. Not picking the latest models is often a great way to save some money as new models cost a lot more.

When needing 4 or more hard drives, it may be wise not to purchase the biggest ones available and save on that too as also here, the biggest hard drives cost a lot more than the next one closest to this size. Especially QNAP and Synology have attractive 5-Bay systems. Both these brands, Thecus and NetGear have 4-Bay systems to choose from. Recommended 4 5 bay (Fat recommended, red Favorite): Synology: DS410j, DS409+, DS1010+ (5bay with expansion option) QNAP: TS-410, TS-410p, TS-439 Pro II, TS-459 Pro, TS-509Pro NetGear: ReadyNAS NV+ Thecus: N4100+, N4200 QNAP is our personal favorite for bigger storage needs with their 6-Bay models and 8-Bay models which luckily exists in different flavors and price tags. The top model (which I currently use), the TS809 is top of the bill but comes at a whopping price. See below for the other models you can choose instead Thecus limits itself to 7-bay NAS in their N7700 series which exist in different versions, the regular, the SAS (not important for you at home) and the PRO which actually adds twice the memory and more processing power. Recommended high capacity storage: QNAP: TS-859 Pro (8), TS639Pro (6), TS-809 Pro (if you can afford it) Thecus: N7700, N7700Pro Synology: DS1010+ and DX510 Advanced users (10+ TB) Now there s another class of users out there, the ones that can t have storage big enough and are hurt by throwing anything out. Some of those will need to go towards custom solutions or self made solutions using free software available online to build RAID, as the big NAS storage devices that come ready out of the box almost are limited to maximum 7, 8 and 10 disks (via expansion). Synology for instance has the DS1010+ for which an expansion to 5 more disks is available, called the DX510. Purchasing these devices both already sets you back about 1.250, bare bone. Imaging 10 disks at another 1.500 and you have one massive storage at a massive cost. The benefit of such systems however is you can spread the investment in 2, start with the DS1010+ and 5 disks, expand later if the DX510 is still available then It seems risky business Same option is available on more affordable units combining the DS509 with the DX5 expansion. It seems however the DS509 is no longer listed at Synology and sadly, Synology s biggest offers is 5-Bay. Let the fun begin: Choosing a NAS The first step in choosing a NAS would be defining a budget and your storage needs. Keep in mind, the storage you need depends on the expectation of what you will do in the near future, let s say, the next 12 to 24 months. You don t want to invest multiple times in smaller NAS which would end up more expensive than going for a bigger NAS immediately. Do not automatically hold the cost of a unit as the main deciding factor as more affordable units usually have its reasons to be more affordable! In day to day use, I m someone who doesn t like compromises Questions you should ask yourself are whether you d want to collect your HD and SD movies, series or will delete these as soon as you watched them. Can you afford the NAS and enough hard drives to get started properly right away? When you delete everything you ve seen afterwards, you probably have sufficient space with a smaller NAS based on a single or 2 hard drives. Then the question becomes if you want a failsafe option for the data or not and whether this would be a MIRROR or RAID0 you can backup externally and manually.

In most cases, especially in these times of HD media, we d recommend going for a RAID5 capable device that can hold at least 4-5 drives to begin with (you can start with 3 disks and expand as you go although we recommend starting out with 4). This makes the investment substantial but it will last you years to come unlike smaller capacity The ever decreasing costs of hard drives have an influence as well Sometimes it s better to invest in a 5-Bay NAS with 1.5TB hard drives than in a 4-Bay NAS with 2TB drives So calculate, research and calculate again Features of a NAS Here comes the deal NAS is more than just storage nowadays These storage devices have enough power and memory on board to take care of more than just sharing data. Current NAS servers include all kinds of media applications that can take away the need for a PC for multiple tasks like downloading files like torrents, UseNet news groups or sites like Rapidshare and Hotfile In almost every case, integrated servers for media are included based on UPnP and DLNA. The server can be installed with additional applications should you own music players, for instance, Logitech music devices using Squeezebox. The server application can be installed serving your music from the NAS to any player in the house over network, including media players. Take a look at the systems some of the vendors provide, like QNAP s QPKG System and Synology s package system... These provide ready to use installations to enhance the capabilities of the NAS server. Besides serving data, most NAS come with applications to backup your data from PC to the server so there s a failsafe backup in case either PC or NAS should break down. You can easily share data within your home network or even the internet. Build your own web server and host your own site it doesn t stop here, but the possibilities go on and on as to how you can make the investment render for you and keep it fun over a long period of time exploring ability after ability at your own pace Size matters Some say size doesn t matter and although in some ways I m sure this is true, in NAS, size does matter. Taking a NAS that offers too low capacity will influence your ability to store data and probably make you invest again after a short period of time Going too far, will mean your investment does not render for you properly as over half the space you purchased goes wasted and consumes power so balancing what you reasonably expect for the coming 12 24 months, is in our opinion the right way to select the investment vs your budget. You could include the fact bigger hard drives may come so you can replace the hard drives and use these later without investing in a new NAS but keep in mind these may not be compatible with your units purchased today and the process takes days to replace a RAID5 with new and bigger disks, having it rebuild all the time and when done, finally be able to expand the volume It s painful. In the end, buy one that lasts you for a couple years and when you grow out of it, look at new options NAS Convenience As with media players, we do have a very strict norm for convenience applied to all our reviews. Hence, I would even agree to the fact our reviews run on convenience a lot. The same is for NAS systems. The ability to download from the internet is a great feature but can it offer Torrent and FTP downloads or Rapidshare type providers all together? Can I schedule downloads to happen overnight were in some countries overnight download volume is only counted half? Does the software that comes with the NAS provide ways to keep my user data of such sites or would I have to reenter my credentials for every file I add? Can I boot and shut down my server on a schedule? Can I schedule this on a daily basis, only on weekdays or is there only one setting that applies to every day? A lot can be different on NAS systems as far as features are concerned. Stating torrent is supported is almost always right, how it is supported remains an open questions until you actually see it at work and it might just not be what you expected being used to a PC application with all the whistles and bells around it. So you need to somehow come up with ways on how you want to use your NAS next to how much money you can spend and how much space you end up needing for a while to come Here are some must haves for me on every NAS I would select GBIT Network, let s face it, we deal with big volumes and files Scheduled up and down time SSH and Telnet (advanced) Internal file manager helps maintain data a lot faster than maintaining it from the PC as data doesn t need to leave the NAS. Internal file copy and moving is a lot faster using an integrated file manager. Option to install additional packages LCD Display (info on NAS like IP, disk space used etc ) iscsi (mapped drive on PC automated) and more

The Future of NAS for us Media Fans Yes it s true Nowadays NAS manufacturers still see NAS mainly for PC world usage and business but the trend started three years ago to incorporate media functions so it can perfectly be used for entertainment storage as well. Although design wise, a lot is left to be desired for real entertainment storage and placing such NAS in your living room (looks, noise), we believe in the near future we may see total different solutions tailored for entertainment that can be used for PC world as well. It s the world reversed If you believe those times will never come, think again. Only recently we came across a DUAL NAS designed for living room from LOOQS. Although we lack details on its abilities and cost, it will come for sure from more brands What the main differences would be between an entertainment storage system or regular NAS is not necessarily software as both will be the same Details are however a 43cm width design that fits in your entertainment rack, passive or very silent cooling, placement of led s must be thought of so they don t create a disco show in your living room, internal design must have softening materials integrated to not carry the rattling of hard drives thru the player and your living room and so on NAS simply is a great device and if you pick the right one, it s an enhancement of your network and media experience for years to come NAS simply has become a part of our daily needs to easily share and store our media Brief Bigger NAS solutions often named PRO include dual network options so these can connect to two networks simultaneously, load balance the traffic or one can purpose as a backup if the other one fails Similar to this system, some NAS have DUAL DOM from which the OS is loaded Should one system become corrupt, it can be restored from the backup or the backup one will take over These are things you can keep into consideration as well should you intend such NAS for more professional use like in hotels and what not or in families with 26 kids and 36 rooms fitted with TV s and DMA players Concluding We don t want you to see this guide as science. There s a plethora of NAS out there and options to build your own, NAS storage based on Windows OS and so on We like to think of NAS for living room use and convenient ones only with low maintenance and clear features that does not require us to fiddle with it all As such, this guide does not pretend to cover all possibilities but offer a way of thinking when approaching a NAS purchase and some basic info to understand all these RAID configurations and options they include I do hope this guide has offered a basic introduction to those with no NAS experience and hope it will trigger a discussion online to offer more ideas, discuss more options and maybe even correct us where we fail to see something important to tell So in the end, I just hope you know more now than you did before reading this article and feel loaded with the right weapons to begin your search for your storage solution of choice For a complete overview of abilities, visit any of the sites and read up on their specifications. Especially Synology and Qnap are the most complete NAS units out there and well worth the investment. NetGear is a bit more limited but Quality wise a very good option and Thecus is rapidly growing to include the entertainment stuff we need, is usually more affordable but integrates less media features at this time. www.thecus.com www.synology.com www.readynas.com www.qnap.com All images, copyright to their respective owners. (Googled a lot) Hi-Jack