wsume99

I too once missed out on a Newegg MIR. I had a $30 MIR for a Corsair PSU that I bought a year and a half ago. I was so focused on getting my new rig up and running with all the tweaks that I completely forgot about the rebate. By the time I remembered it was too late - damn 21 days. I was pissed about that one for a while. For this reason I usually ignore the MIR when deciding to buy an item. If it's not worth it based on the purchase price I probably won't buy it. Then if I get the MIR that's just icing on the cake.

^^Thanks for the reply Bob. You just saved me $1.29. IIRC WD is the only mfg where you need to use jumpers to disable 4kb sectors.

I was wondering that myself, which pitch was correct?

For most 2TB drives the preclear & parity sync process might take about 35-40 hours to do. Now although it's not a week like the study used but for that period of time the drive would have to be classified as high utilization. How could it not, it's using 100% of it's bandwith? Granted it's not for an entire week but I was speaking about the period of time that it was preclearing. This is really irrelevant since this study of over 100,000 drives already concluded that drive utilization had no correlation to failure rate. Now maybe higher utilization would lead to a higher URE rate and potential data loss but as the MS study we previously discussed showed there was no correlation there either.

I'm very interested in this as well. I'd like to consolidate my PVR and unRAID server into a single box if possible. The only problem is that I'm a total noob when it comes to stuff like this. Is there a guide out there that anyone knows of that might get me started?

Yes it does. See paragraph 3.3 - Utilization for their definition of utilization. So according to their definition preclearing a disk would be high utilization since it is using 100% of the disk's bandwidth throughout the process. (Correct me if I'm wrong Joe L.) Wrong again. These hard drives were employed only in rack-mounted servers. The disk population is described in paragraph 2.2 - Deployment Details. Did you read the article that you cited?

Try this page. It should get you up and running. I know that it was sufficient to get me up and running. Which means that a monkey could do it then.

I've actually scanned through that paper before. I wish they would have published the data by mfg so we would know which drives performed the best. But they purposefully decided to mask the mfg info from the results (most likely to avoid any legal liability) and only do analysis on the aggregate data. This time I read it in more detail. There is some really interesting stuff in there. I believe that most unRAID users purchase OEM drives which means that the equipment manufacturer's stress test would not be performed. So if you're using an OEM drive and are hoping to see similar failure rates then you'd better be doing some burn-in testing. Even more of a reason to run preclear on a new OEM drive. So their findings indicate that high utilization is not correlated to higher failure rates. Doesn't this disagree with your point KYThrill? I believe you are trying to make the point that the more you use (i.e. read from) a drive the sooner you are likely to encounter an error which will eventually lead to a failure.

So Canadians get free healthcare but Americans get better deals on power supplies. God bless the USA!

This is so right. I forgot to remove the jumper from the WD20EARS drive I just RMA'd (oops), so now I'm out of jumpers. I found a 24 pack of jumpers online here for $1.29 and they wanted $6 to ship it to me. Now I'm looking for a local source of supply.

Just FYI - I did a quick search on monoprice.com and here is a quick comparison of the cost of Cat5e vs. Cat6. Cat5e 1000ft bulk cable: $65.10 Cat6 1000ft bulk cable: $86.71 Cat5e keystone jack: $1.21 Cat6 keystone jack: $1.43 The prices I listed were for an order quantity of 1. Each item has discounted prices if you order more than one. You can get 1000 ft of cable and 10 keystone jacks for $100 using Cat6 vs. $77 for Cat5e. As I said before all the other hardware would be the same (wall plates and low voltage boxes) and there should not be any difference as far a labor is concerned. So the difference in price from your installer should be pretty small. Hopefully your contractor doesn't try to pull a fast one on you.

Here is a good 550-watt PSU: CORSAIR CMPSU-550VX 550W It's $90 + $6 Shipping w/ $10MIR. But I'd actually suggest you go with this one: CORSAIR CMPSU-650TX 650W It's $90 + $2 Shipping w/ $10 off Promo Code + $10 MIR. It's a higher wattage than you wanted but it's cheaper. More is better, right?

I cannot agree more. If you are going to fork out money to install a wired network in your home then by all means purchase Cat6 cable and sockets. If you're paying someone to install the network there should be no difference in installation cost, at least there shouldn't be if you're using a good contractor. The only difference is the h/w cost and the difference is not that big. I personally ran Cat6 in my house about 18 months ago and for 500 ft of cable and 6 sockets IIRC it cost me about $50 more to run Cat6 vs. Cat5e. It might even be less now. Well worth the investment and peace of mind knowing that my wired network is good for a long time.

I don't have a copy of the MS report that you are speaking of but it seems as though you might be misinterpreting what it is saying. I don't agree that it is statistically significant. In fact the data that you cite is problematic. You quote MS... What basis does MS have to say that drive failure rates are more than 10 times too optimistic? Both tests conducted by MS yielded an actual URE rate that was much lower than the vendor's predicted URE rate. This is supported by their ultimate conclusion. Seems like there is a simple explanation for their findings. The programmer perspective they speak of is how often the drive cannot provide an accurate response to a query from an external source (i.e. program request for data). The drive perspective would be internal read erros that occurred, some of which were masked at the programmer level because the read was probably retried and accomplished successfully. So my interpretation of the data is that the drives experienced 30 raw read errors, 5 of which could not be corrected and became UREs. ON AVERAGE each bit had been written to 140 times, however the test used 10GB random writes in a random pattern. So STATISTICALLY speaking there would be many bits that experienced very few reads(i.e. <10) and likewise many other that had much more than 140 reads. Heck statistically there could be some bits with over 100,000 reads. Perhaps the errors only occurred on the bits that experienced an unusually high number of reads. Correct. Based on the test it is a fact that every bit was read 945 times. Wrong. As I said above, on average each bit was read 140 times, however we know that due to the randomness of the reads that some bits would experience much more than 140 reads. In fact there are many that probably exceeded 945 reads (the frequency seen in the second test). And some that were even higher. I disagree. There is insufficient evidence to support such a conclusion, but I am willing to agree that it might not be the only contributor. I'm surprised that the almighty MS did not have a better DOE (Design of Experiment). They ran two tests and based on the outcome of both cannot determine if there is a correlation between the numer of times a specific bit is read and UREs. That's lousy engineering. No wonder their products are so overpriced and rife with defects. They are probably wasting lots of money doing stupid things like this instead of making their products more robust.

I'm glad I'm not the only one to think that it's a little far fetched to suggest that a 2TB drive can be worn out after half a dozen preclear cycles.

Well if I follow what was written above running a single preclear cycle on a any 2TB Seagate, Hitachi, or WD Black HDD and then adding it to the array will put it about 50% of the way towards having a read failure and possibly being identified as a failed drive by the array. I happen to agree with you, bjp999, and I'll keep running preclear on all my new my drives. It does weed out the bad ones and makes sure you have everything squared away before adding it to the array. I believe the benefits of running preclear far outweigh any possible "wear" that the drive may experience.

KYThrill, I understand the logic behind your argument however I'm betting that your definition of usage and the OEM's definition of usage are different. There is a distinct difference between reading the entire drive several times (say 6 times for a 2TB 10^14 drive) and getting a failure and traditional HDD usage where a high number of reads are going to be concentrated on a small subset of the total bits. Your scenario is on one edge of the spectrum. The other edge is to assume that we pick just one bit on the drive and read it over and over again until we experience a URE. Theoretically we should be able to read that single bit more that 10^14 times before we encounter an error. However I'm betting that it will fail much sooner. You really need to take a bit level perspective. Your scenario has the drive failing after all the bits on the drive have been read 6 times but the example I just laid out has a single bit being read 10^14 times before failure. There are so many different ways to interpret the OEM's nebelous URE rate specifications. In my view a URE would be attributed to a bad bit on the physical disk which would only be encountered after a high number of read cycles on that individual bit and most likely there would be read errors (not unrecoverable) before the URE occurred. The OEMs URE specification probably assumes that the bit reads are concentrated on certain areas of the drive (aka usage profile) not spread evenly across the drive like during parity checks and preclear cycles. As evidence that your conclusion is faulty I submit to you the posts on this forum. If failures occurred at the rate that you suggest we would see hundreds if not thousands of posts concerning failed disks during parity checks and unRAID would not be as popular as it is.

Exactly. That's why I've decided that I'm only going to add 2TB drives from now on. It's way more economical for me to pay a few extra dollars and get the bigger drive than to have to add an expansion card or build a second server.

That's awesome. Did the HPA option show up as BACKUP BIOS IMAGE TO HDD in your BIOS?

I currently have 2 Gigabyte AMD MBs (one in an unRAID server) and both of them have a BIOS version where HPA is disabled by default. You have an Intel board so YMMV. I went through exactly the same ordeal you are and was really concerned by all the things that the experts said on this forum about HPA. Some of the newer BIOS releases by Gigabyte have HPA disabled by default. If you can find a newer BIOS version where it is disabled by default then your board is perfectly fine for use in unRAID. The HPA setting on my boards was under the ADVANCED BIOS FEATURES screen in the BIOS. The parameter is called BACKUP BIOS IMAGE TO HDD. It has to be set to DISABLED. My boards have a default value of DISABLED. Go ahead and check your current BIOS to see if a setting like that exists. I checked the manual for your MB and there is not such option shown so odds are that you may be out of luck. My suggestion, like Joe L’s before me, is that you install the latest BIOS version available for your board which currently is F5f released on 8/25/2009. If that doesn’t work then you’ll need to find another board. There are three possible outcomes to your current situation: 1) You cannot find a BIOS version that has any option to adjust HPA settings so you are stuck with HPA on. In this case I’d say you need to use a different board. 2) You find a BIOS version that does give you the ability to disable HPA but it is not disabled by default. In this case you can disable HPA and use the MB in this condition however it is risky. If the CMOS battery were to fail all of your BIOS settings would be reset to their defaults, so HPA would be turned back on. This is what Joe was describing. Doesn’t happen a lot, but it does happen and if it does you could, NOT WOULD, lose some, NOT ALL, of your data. I'm guessing you are building an unRAID server because you want all your data in a centralized, SECURE location. This condition makes it less secure, how much less, well that's debatable. 3) You find a BIOS version that does give you the ability to disable HPA and it is disabled by default. In this case just make sure you have it disabled and you NEVER change it. This is the only situation under which I personally would use the board.

No problem. Considering all the help I've gotten from the users on this forum I guess I feel like it's the least I can do. Hopefully it will help someone else get their first unRAID server going. It was amazingly easy. If you can follow instructions (which I believe is a kindergarten skill) they you can build an unRAID server. I'm planning on working towards Level 2 but I've got a few other irons in the fire now that need attention plus I just had to RMA my new WD20EARS drive so it'll be a few weeks before I can start adding more drives anyways. You can view my syslog for Level 1 certification here.

Built my first unRAID server using a board I already had. It's a Gigabyte GA-MA785GM-US2H rev. 3.3 with F11 BIOS and an AMD Sempron 140 that I can't get to unlock the second core. HPA is disabled by default in my BIOS version so I'm safe there. I'll post more info about the system later. Attached is a copy of my syslog from cold boot including an error free parity check. I think that satisfies the Level 1 certification requirements. syslog-2010-09-29.txt

I've read that before. That's why I'm asking. I assume the fact that it has successfully checked parity is sufficient proof that it has computed parity. So all I need in the syslog is the boot sequence and a successful parity check. Correct?

So I assume that you did not purchase unRAID then. I'd do exactly what you mentioned. Start small and get the basic version up and running with two data drives and a parity drive (use a 2TB drive for parity if you have one). I think starting small will make it easier to get your new h/w up and running. I don't know what size drives you have but with 3 2TB drives the basic version can hold 4TB. Once it's stable then purchase a license and start moving more discs over from your existing server.

It's not clear to me, do you already have a unRAID machine running? If you don't I'd suggest getting your new h/w up and running using the basic version first and then expand/upgrade to the standard/pro version depending on your needs. That's what I plan on doing. I've got my basic system running pretty stable now and plan on upgrading in the near future. If you do and you're using the basic (free) version then you can move the files from one USB drive to another. Just prepare the drive like a new install and instead of copying a new unRAID version onto it copy over the contents from your eisting USB drive. If you're already purchased the standard or pro version then it is locked to your USB drive. So if you copy the files onto another USB drive it won't work.