New to unRAID, little advice needed :)

[HKR]

Hello,

 

After a lot of carefull consideration and looking around i decided to take the leap and go for unRaid on my server. My parts are about to arrive in a weeks time. I have decided to go for these:

 

Gigabyte H87M D3H (yes, i looked into the HPA issue but cant find any users facing problem with this board)

2 x 4GB Gskills DDR3 1333

Intel G3240 3.1GHZ 53W TDP

Fractal Design Node 804

Corsair CS550  550W SMPS

3 x 4TB + 4 x 2TB  (1x 4TB for parity)

 

Now i do have a few questions, though most are answered in the videos linked on the forums but i still am confused.

 

1) Do i need to use a cache drive (SSD) ? Or is it needed only when there are a lot of HDD's ?

 

2) If i make a folder say 'Movies' and dump all my movies into it, can i dump more data into single folder then the size of a HDD? What i mean is that if my biggest drive is a 4TB can my movies folder be say 5TB? In this case my data will get written on multiple drives?

 

3) The above condition where which data is written to which drive is decided by the parity drive?

 

4) Can someone link to to material/guides regarding plugins and add-ons that can be installed on the unRaid server?

 

5) If a drive fails do we need to make some changes to let the unRaid server know we shall be replacing the drive or just replace the drive?

 

6) Can a parity drive be replaced by a larger size drive and later the old parity drive can be used as a data drive?

 

Thanks

[meep]

I'll take a stab at this for you, though I'm sure someone more knowledgable will chime in with finer detail;

 

1) Do i need to use a cache drive (SSD) ? Or is it needed only when there are a lot of HDD's ?

 

You don't need a cache drive. It's optional. Whether you need one or not is not really dictated by the number of HDDs you have but by the amount of writes you perform and how fast you want those writes to take place.

 

Without a cache, all data needs to be writhed to both the target HD and Parity drive (I think this involves two writes and a number of reads). This can be a slow process.

 

The cache drive acts as an intermediary, data write to the array is written once to the cache drive. This is a faster process and, if you used SSD for cache, very fast. However, you're only postponing the actual array write and in ted period that your data sits on the cache drive before being moved to the array, it is unprotected. (if the chase drives fails, you lose your data).

 

The migration of data from cache to array is an automated process - you can set the parameters but it typically takes place once a day.

 

In a case where you're setting up a new array, you probably don't want to use cache as you'll probably fill it up quite quickly anyway.

 

If using a cache drive, you have the option of setting up shares that are restricted to cache only or set to not use cache so it's quite flexible.

 

 

 

2) If i make a folder say 'Movies' and dump all my movies into it, can i dump more data into single folder then the size of a HDD? What i mean is that if my biggest drive is a 4TB can my movies folder be say 5TB? In this case my data will get written on multiple drives?

 

I like to think of my users shares as folders. You set up a user share and tell unRAID what drives you'd like it to span (default is all drives). So you can keep filling that folder/share even beyond the capacity of a single physical drive. UnRaid is very flexible in how it lets you set drive fill-up as well. You can start with the first, fill that up, move to the second etc. Or you can keep filling until all drives are at 50% and then go back to fill all to 75% etc. for better distribution of data across drives.

 

You can also set up your shares to configure the sub-directory level which gets split across drives but we're probably getting ahead of ourselves there!

 

 

 

3) The above condition where which data is written to which drive is decided by the parity drive?

 

No, this is configured by you in setting up your shares. The parity drive / functionality has no role in this.

 

 

 

4) Can someone link to to material/guides regarding plugins and add-ons that can be installed on the unRaid server?

 

This is scattered all over the forums, unfortunately and now that we have various flavours of virtualisation as well as plug-ins it's a broad topic.

 

 

 

5) If a drive fails do we need to make some changes to let the unRaid server know we shall be replacing the drive or just replace the drive?

 

Not really, you simply assign a new drive to the slot and provided it's the same size or bigger than the failed drive, unRAID will rebuild the contents from it's parity data.

 

6) Can a parity drive be replaced by a larger size drive and later the old parity drive can be used as a data drive?

 

Yes. I've gone from 1TB parity to 2TB parity to 4TB parity in the last few years and recycled the 'old' parity drive to the array each time. The only caveat is that you'r array won't have parity protection while you do this as the new parity data needs to be built.

 

Hope that helps a bit?

 

[HKR]

thanks a lot, it cleared up a lot of confusion.

 

One question, I read somewhere that unRaid for optimum performance needs around 1Gb ram per TB, is that true?

 

Can you comment on my NAS config i posted, is there somethings i can change or do you have better suggestions for improvment?

 

While i was over at another OS forum, people recommended me to get a Intel Gbit NIC and not use the on-board realtek, does this seem to be the case with un-Raid too?

[itimpi]

thanks a lot, it cleared up a lot of confusion.

 

One question, I read somewhere that unRaid for optimum performance needs around 1Gb ram per TB, is that true?

Not sure where you saw this?  maybe it is talking about some other form of NAS storage?

 

For basic NAS functionality with unRAID v6 you could get away with around 1-2GB RAM in total regardless of the amount of storage  (in fact a basic v5 system can be run in 512MB).    Having said that more RAM can improve performance and become s a necessity if you want a lot of add-ons or to run Virtual machines.    I would think that something like 4-8GB is a sensible minimum for general use, and if you are going to be into Virtualisation technology or running a lot of add-ons it may be worth having something in the 16-32GB range.

 

While i was over at another OS forum, people recommended me to get a Intel Gbit NIC and not use the on-board realtek, does this seem to be the case with un-Raid too?

Some versions of RealTek have had problems in the past.  Having said that I use my on-board RealTek without issues.  My suggestion would be to see if when you boot up unRAID it sees your on-board RealTek OK, and only consider getting an alternative card if you have problems. 

[boof]

One question, I read somewhere that unRaid for optimum performance needs around 1Gb ram per TB, is that true?

 

Whilst this isn't specifically true - unraid will run with less and certainly without a linear scaling of memory per TB - if you plan on using the cache_dirs plugin (which is a very good idea) then the more memory you have the better. And you will likely want more memory the more files you have on your system.

 

cache_dirs caches filesystem metadata in memory to improve the browsing experience and avoid disk spinup where possible. I imagine this is what's led to the above recommendation. Though it should really be based on file count rather than file size.

[itimpi]

That figure of 1GB per TB would only make sense even with cache-dirs. installed if you had millions of tiny files.  You would need nothing like that for a server that is primarily storing media files which are comparatively large.  I know of people who have 50-100TB of storage and run quite happily with 4GB of RAM.

[CHBMB]

thanks a lot, it cleared up a lot of confusion.

 

One question, I read somewhere that unRaid for optimum performance needs around 1Gb ram per TB, is that true?

 

Can you comment on my NAS config i posted, is there somethings i can change or do you have better suggestions for improvment?

 

While i was over at another OS forum, people recommended me to get a Intel Gbit NIC and not use the on-board realtek, does this seem to be the case with un-Raid too?

 

1GB per TB is what is recommended for FreeNAS, and I seem to recall it requires ECC RAM & Motherboard.  Which makes the hardware a fair bit more expensive.  I think that most of us on here run on far less memory than that rule, my last UnRAID box had about 20TB on it and I was using 4GB. My storage hasn't really increased since then, but I now have 32GB because I got a good deal on it and I'm playing around with virtualisation more, but that's another issue.

 

If you're new to NAS and storage in general I would stick with UnRAID, and I've tried WHSv1, WHS2011, Transparent Flexraid and have just come back to UnRAID because it's simple, easy and I trust it.

 

My advice is take things one step at a time.  I personally think a cache drive is pretty much a necessity, however that's largely because of how I use it, my cache drive is a regular HDD but I do have an SSD mounted outside my unraid pool.

 

1.  Get an array up and going.

2.  Look at plugins and dockers, personally I think dockers are likely to be the way forward and install one at a time and take things slowly.

3.  Once you've got this far then think about what else you want to accomplish, odds are, someone on the board has done it before and they'll be info around, and it's a friendly community with lots of help around.

 

In answer to your questions:

 

Parity acts as an "insurance policy" if you like, it insures you against the loss of one data disk, it needs to be at least the same size or bigger than any of the other data drives (not cache)  It can be upgraded easily for a bigger one at any point and the old drive can indeed be used in the array as a data disk.

 

Your hardware looks good to me for a decent NAS.  As far as I can tell, you wouldn't be able to virtualise with it, other than Dockers and possibly VirtualBox, but that may not be something you need or want.

 

It might be better to have told us what you want to do with your server then we could have recommended a direction to take, but I can say for certain that your hardware is a LOT better than I had on my first UnRAID server, I can't remember exactly what I had other than the motherboard was the Supermicro C2SEA (LGA775) with 4GB RAM and some sort of Intel Core 2 Duo. UnRAID ran fine on that..

 

I still use the Realtek onboard NIC and can't say I've noticed any problems, why don't you just try and see, can always add in an Intel NIC at a later date.

[HKR]

Your hardware looks good to me for a decent NAS.  As far as I can tell, you wouldn't be able to virtualise with it, other than Dockers and possibly VirtualBox, but that may not be something you need or want.

 

It might be better to have told us what you want to do with your server then we could have recommended a direction to take, but I can say for certain that your hardware is a LOT better than I had on my first UnRAID server, I can't remember exactly what I had other than the motherboard was the Supermicro C2SEA (LGA775) with 4GB RAM and some sort of Intel Core 2 Duo. UnRAID ran fine on that..

 

 

 

- Do you mean not recommended for Virtulization because of low RAM or do you see any other issues?

 

-Thing with hardware is that where i live its very hard to get server grade hardware and ever desktop based H/w is far more expensive then what you'd pay for the same in UK/US. That is why i tried to choose the best i could after looking around everywhere. For exampale i am paying around $180-200 for WD 4TB Greens and that too only one Retailer i know has it in stock.

[HKR]

I am thinking off swaping the Gigabyte mobo with ASUS H87M-E LGA.

 

Do you think its a better choice?

[trurl]

...Do you mean not recommended for Virtulization because of low RAM or do you see any other issues?...

The G3240 does not do vt-d so will limit your ability to directly access the hardware from a VM.

[HKR]

Is there any way to number or find out which drive selected in unRaid as data and which is parity in the drive cage inside the cabinet if say i got 6-8 drives of the same size and brand?

[JonathanM]

Is there any way to number or find out which drive selected in unRaid as data and which is parity in the drive cage inside the cabinet if say i got 6-8 drives of the same size and brand?

unraid identifies drives by serial number, so you should be able to use that to cross reference. Some people make labels with the serial to stick to the drive in a more visible area to help with that.

[HKR]

You mean the S/N on the HDD is used to identify the disk in unRaid? Then its fairly simple

 

Also, can someone pls tell me if asus mobo is better for unraid then a gigabyte one? The latter is slightly cheaper so i can order one accordingly.

[trurl]

Is there any way to number or find out which drive selected in unRaid as data and which is parity in the drive cage inside the cabinet if say i got 6-8 drives of the same size and brand?

unraid identifies drives by serial number, so you should be able to use that to cross reference. Some people make labels with the serial to stick to the drive in a more visible area to help with that.

And unRAID displays these serial numbers in the webGUI.

 

All the drives I have bought lately actually already have a sticker on the end (opposite the connectors) with the last 4 characters of the serial on it. Depending on your drive cage you may be able to see these without removing the drives. I know I can with mine.

[CHBMB]

Personally, I'd go for the Asus board because it has 4 x PCI-E slots versus 2xPCI-E and 2xPCI on the Gigabyte board.

 

The Asus board supports Vt-D for virtualisation BUT you would need a different CPU that also supports Vt-D.

You could get the Asus board & your original CPU and if you wanted to experiment with virtualisation at a later date then upgrade your CPU.

 

Someone else may have a different opinion.

[HKR]

I am trying to get hold of the Asus mobo however it seems to be out of stock everywhere i check. Do you think the gigabyte board will have the HPA issue or is it limited to older models only? Any way to check for this issue before i place an order for gigabyte?

[CHBMB]

I have absolutely no idea if the HPA issue is still a current thing or not.  I vaguely remember having a problem with it on my first server build but that was over three years ago. 

[HKR]

The problem is only gigabyte is available in my country easily. Asus isint available anywhere i looked

 

Also upon googling about the HPA issue it mainly comes up with threads on unRaid forums and elsewhere it seems no one knows this issue exists.

[JonathanM]

Also upon googling about the HPA issue it mainly comes up with threads on unRaid forums and elsewhere it seems no one knows this issue exists.

It's not an issue for most uses. Windows for example doesn't care if the drive is suddenly a couple K smaller than it was last boot. The reason it's a big deal for unraid is that the entire drive is used for recovery purposes instead of just what portion is actively holding files. This brings up another difference, in that unraid needs the drive to operate flawlessly end to end if it is to be used to recreate a failed drive. Many times a drive will have a few defects that are never an issue for a windows box, because that portion of the drive never gets used, but that same drive would cause errors in an unraid server. Drives that are to be used in unraid should be tested fully, either by the manufacturers diagnostic software, or in the unraid box using the preclear script available here on the forums.

[HKR]

I understand all that however i am unable to check with the manufacturer's site if the issue is present in the current board i wish to order.

 

Anyway i can check myself?

[Squid]

If there's a BIOS option in the manual for it called something like backup bios to hard drive then it will definitly create the hpa unless you disable it.

 

Both of my gigabyte boards do not give me the option to disable it.

 

IMHO the problem is a bit overblown.  As long as one of the hard drives connected to the motherboard already has an HPA on it, the bios will not create another one.  On a data drive HPA is irrelevant.  Parity drive its going to affect.  (which is why I make sure that one of my data drives always has an HPA on it - to the extent that I will force HPA to go onto a new drive if none of the other drives connected to the motherboard have it)

 

Also, I've found that the only time the HPA gets written is when the system fails to boot from the flash drive and attempts to boot from the hard drives.

 

 

[HKR]

Say the problem is in the mobo i order, can i overcome it if i install the data drive first on the server and then setup the parity drive?

[Squid]

Say the problem is in the mobo i order, can i overcome it if i install the data drive first on the server and then setup the parity drive?

Boot the mobo with no drives attached.  See if there is an option somewhere to disable backup bios to hard drive.

 

If there's not, then what I would do to protect the parity drive from getting HPA put onto it would be to install one data drive into port 0 on the mobo and try and boot from it (no flash drive)

 

HPA should get put onto it.

 

Continue setting up the system.  All further drives *should* not get HPA put onto them even in the event of a flash drive failure.

 

As long as any new drives are not put into other computers first before preclearing, etc they will stay clean.

 

Not 100% a given, but that's been my experience

[HKR]

Thanks for the clarification.

 

I was looking into sata controller cards as i would need one due to lack of enough sata slots on my mobo. Then i came accross something called a sata multiplier card, what it seems to do it multiply your 1 sata port into 5, so you can hook up 5 sata HDD through that card. Do these things actually work? I dont want to get a raid card as it would shoot up my budget a lot.

 

 

[JonathanM]

IMHO the problem is a bit overblown.  As long as one of the hard drives connected to the motherboard already has an HPA on it, the bios will not create another one.

So what happens if the HPA hard drive is the one that fails? Now you've got your motherboard creating a HPA on one of the drives that is needed for the recovery.

 

Yes, it requires a perfect storm of failure to actually bite you, but if it does you will not be saying the problem is overblown.