Setting up ARC 1200


Recommended Posts

  • Replies 56
  • Created
  • Last Reply

Top Posters In This Topic

I did this so long ago, so forgive me if it's vague.

 

I remember making the two drives a raid set.

Then I remember creating a raid volume set. First was a RAID0 volume set (my size was 2.2tb).

It did ask me something about 64bit LBA's I did not enable it, but I also was not going larger then 2tb.

Then I created a raid volume set, this was RAID1 with the leftover space.

 

I believe I went into each of the raid volumes and set spin down to max which was 60 minutes.

Perhaps it was the raid set, I cannot remember.

 

So first step is to make a raid set.

Then make the volumes each of a different type of raid.

 

unRAID sees the volume sets as different drives.

There is no SMART information available and I think the spin down timers on unRAID need to be disabled.

The id's will look funny in unRAID, but I just live with it.

 

That's all I can remember. I know bjp999 did the same thing with different drives and sizes.

I'm sure he will chime in.

 

Link to comment

I had to do a ROM upgrade to v1.49 immediately to recognize my 3T drives properly.  I have 2 3T drives, configured with a 3T parity (RAID-0), a 2T mirrored pair (RAID-1), and a ~1T "cache" (RAID-1).  The mirrored pair is not used in unRAID - it is suitable to backup important data that is more secure than unRAID.  It also has faster writes.  I manually mount it and create my own Samba shares on it.  Each person in my household has their own "home" directory on it that they can use to store important data or copy files for backup.

 

I did not like having my cache drive shared with my parity drive on the ARC-1200.  Any I/O between the cache and the array is impacted.  So that space is not being used right now. 

 

I had a grand plan to use HPAs on my ARC-1200 volumes.  I could create a 4T volume, use HPAs to reduce it to 3T, and then remove the HPA once I wanted to use the 4T parity.  But I could not create the HPAs on the ARC-1200 volume.  I don't think there is any reason you'd go there, but thought I would report it here.  If you have a 4T parity and your max drive is 3T (or 2T), you could severely impact your parity check speeds.

 

Like WeeboTech, I don't remember the exact steps - maybe you could document them as you go through?  I do have some notes from some PMs with Weebo.  It asks you whether it should do foreground, background, or no initialization.  I think I selected background (which took a while), but Weebo said I should not have to do any initialization but I had already started it.  I do remember it taking some time to figure out how big to make my parity to be >=3T.  My first attempt was way too big, so I did it a second time to make it smaller (I'm miserly with my disk space  :)).  It is still too big, but only a little bit.  You can't get it perfect because of the increments it uses (percentage I think).

 

As Weebo says, the drives show up with funny IDs, and don't spin down or report smart data.  You just have to live with that.  I set my parity to manual spindown.  You could probably hook one of the drives up to another controller to get a smart report, but I've always feared that it would somehow corrupt the volume.  I don't really think this would happen, but was not sure enough to try.

 

The performance is quite nice.  I am very happy with mine.  Plus the ability to create a large parity volume (4T, 5T, ...) using smaller drives means that you can buy a single larger disk (e..g, a single 4T drive), up your ARC-1200 parity size, and be able to use the full capacity of your new monster drive.  It has been a pain to have to buy not one but two of the next larger drives to get any advantage, and this solves that issue for me.

 

Good luck.  Let me know if other questions.

 

(Sorry for my tardy response.  Was away and didn't see until today.)

Link to comment

So why does this card work so well for Raid0 of the parity drive but not the M1015?

Is it the processor, or does the Areca have a cache?

 

The ARC-1200 does its thing 100% in firmware.  There are no required drivers, so it is 100% invisible to the OS.  Not sure about the M1015 in this regard. 

 

The fact that the ARC-1200 allows an option to spin down the disks after a period of inactivity combined with the fact that Weebo had used it successfully was what made me purchase this card.  I also was looking for a 2-port card.

Link to comment

I can understand that any I/O on the Parity drive will have an impact the Cache drive performance and vice-versa.

 

The drives are shared between Parity and Cache, there is denieing that(I hope that ir proper English, Iam a Dutchie.

 

Maybe Weebo has some info on this performance-loss?

 

I don't have the numbers, but remember the impact was significant.  Writes to the cache were fast and protected, but if you are trying to write to cache at the same time you are writing to an array disk (any array disk), you will see a serious slowdown.  But impact depends on how you use your array.  If all of your writes to the array are cached, then you may get the best of both worlds - so long as there are enough hours in the night to copy the cache contents to the array (speed of this will be impacted since you are reading from the same physical disks as the parity disk is reading/writing).  But in my usage, it wasn't working out.

Link to comment

I can understand that any I/O on the Parity drive will have an impact the Cache drive performance and vice-versa.

 

The drives are shared between Parity and Cache, there is denieing that(I hope that ir proper English, Iam a Dutchie.

 

Maybe Weebo has some info on this performance-loss?

 

I don't have the numbers, but remember the impact was significant.  Writes to the cache were fast and protected, but if you are trying to write to cache at the same time you are writing to an array disk (any array disk), you will see a serious slowdown.  But impact depends on how you use your array.  If all of your writes to the array are cached, then you may get the best of both worlds - so long as there are enough hours in the night to copy the cache contents to the array (speed of this will be impacted since you are reading from the same physical disks as the parity disk is reading/writing).  But in my usage, it wasn't working out.

 

It's exactly as bjp999 states. If you are writing or reading from the raid1 volume on the raidset and accessing the raid0 volume on the same raidset they will compete for I/O.

 

In my house, I am the only user. I know this and I select where and when I am going to write.

 

The Areca controllers have a ram cache. you can enable write back cache, but that should be used along with A battery backup unit. In my case, I do not use it with one. I've been alright, but I would not suggest this normally without a BBU or a UPS.

Link to comment

I won't be doing very much writing myself. I will use the cache disk for some apps, SABNZB mainly, which is setup so that downloads will initially be saved to the cache disk and then moved at night to the array.

 

My guess is that after the initial parity check is finished it will be updated when changes are made on the array.

 

Link to comment

At the moment I have my server running with a 3TB parity drive.

 

When I put 2 2 TB drives on the ARC1200 can I then create a RAID0-volume that is big enough to replace this 3TB drive?

 

I want to use the remainder as cache drive, should I create this RAID1-volume first?

 

Depends what you want to be the fastest.

I think I created the raid0 volume first. that way writes to the array occurred at top speed.

The raid1 volume was created with whatever was left over. Which was fast enough for cache and apps.

 

 

How do I replace the current parity drive with this newly created volume?

Are there any precautions to take into consideration before starting whith this?

 

stop the array, reassign the parit drive to the new drive, start the array.

Precautions? None I know of, I would not write to the array while this is going on.

 

When one of the drives on the ARC1200 goes bad, how difficult is it then to replace this drive?

 

I've not had to do this, but I'm guessing the drive will need to be replaced, then you will need to go into the bios and rebuild the array.

Link to comment

I guess I just wait till SABNZB finishes its job then move all finished downloads to their final destination on the array(this normally will happen automatically during the night, but I might do this manually) and backup the files on the cache-drive to a folder on the array.

 

Just a bit of an uneasy feeling, if one of the drives on the on the ARC1200 goes, you will loose both parity and cache drive. Or will the data on the cache drive remain intact since it's RAID1?

Link to comment

If you loose a drive on the ARC-1200, you will loose parity, The cache drive was protected and will now be unprotected.

At that time I would execute the mover and/or backup the cache drive, then replace the failed drive.

 

You may find the regular unRAID array fast enough in that you do not need to use the cache drive for temporary storage.

With a bit of tweaking that was my findings. I hardly use the RAID1 cache drive except to store apps.

Link to comment

I still want to keep SABNZB doing its stuff on the cache drive (downloading, checking, repairing, unpacking), or do you know a better place to do it?

 

Then keep it there. keep in mind, there will be competition when moving files from cache to parity protected array.

If both the RAID1 cache and the unRAID array are being heavily written to, there will be performance issues.

Link to comment

So far I have updated the firmware to 1.49 on the ARC1200.

 

connected 2 wdears drives to it, 2x 2TB

 

created a RAID SET, total size 4 TB

 

tried to create a volume of 3 TB, but cant go any higher then the default size of 2 TB. I selected 64bit LBA, also had an 4K option, but didn't select it.

 

My question is: did I oversee/forget something?

 

Link to comment

Selecting the 4K option did it, maximum volume size is 4000 GB, I edited it to 3000GB. RAID0, stripe size 64K,

 

After that I created a RAID1 volume of 1000/2=500 GB. It came back with a question to initialize or not. This didn't happen when creatin the first raid0 volume.

 

So now I have a 3000GB raid0 and a 500 GB raid1 volume.

 

Thanks so far Weebo.

 

 

Link to comment

do us all a favor.

 

With a new data disk or one that is fast and mostly free along with the new parity, do a writeread10gb test to the new data disk that uses the RAID0 parity and also do it on the cache when there is no activity.

 

see my sig for the link to my google code page.

Link to comment

do us all a favor.

 

With a new data disk or one that is fast and mostly free along with the new parity, do a writeread10gb test to the new data disk that uses the RAID0 parity and also do it on the cache when there is no activity.

 

see my sig for the link to my google code page.

 

I currently am building a new server and have the ARC1200 plus 2 disks in the server. Can I run this 10gbtest on the free version of unraid which has no support for a cache drive? I can add a 7200 rpm Samsung 1 TB drive for testing purpose. Is this 10gdtest just some script? How do I run it?

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.