Is conversion from Stripe to Raidz1 or z2 possible?

[nasnice]

Good morning,

To further clarify the question a little background.

Got here a PC with Win7 that I used as a media file server for the children, 2 x 3 Gb WD reds. Simple and easy until you want more (Shares for satellite receivers, etc.) So looked for a NAS solution and ended up with Freenas. Works easily and clearly. Because the kids data was not unique I chose a stripe config and made mounts with the categories (movies, animation, sound, etc.) After the first test, I built a dedicated Freenas server using the best buy Tweakers guide from the NL. Unfortunately without ECC memory... I added an additional disk 3 TB and started with transferring the data from the children.

So now I have a ZFS stripe of 3 times 3 TB with one principal mount and some submounts; total 2.7 Tb free.

All works perfect, nice and fast and smoothly to date.

But now I want more and I started combing this forum and read the "Freaking" manual ...

And then I realized I made an error. I now want to actually put my serious data on the NAS so that I as well as others have access to that (FTP etc.) While I do backups from my present data it would be nice to have all data safely online in a raid config.

But with serious data comes the concept of data security. I'm a little shocked that the ZFS file system apparently is rather fragile, eg power failure (which still happens here one or two times per month, hence the BBU unfortunately unmanaged) can in turn lead to the loss of ALL your data. Is Freenas not trying to limit the damage as it gets the power down signal from the PSU?
I have also read that there are no good tools to repair your ZFS "pools" should they fail.

Hence the need for redundancy that should be realized in the form of a RAID configuration. Now The preliminary goal is to have a total Raidz of 12 GB.

So now my real question:

Can I convert my current stripe of 3 disks simple to Raidz1 or z2 configuration by adding additional (3GB) discs?

Am still a noob in unix, secondary objective of this exercise is to also learn some unix ...

 

[Ericloewe]

No, you have to backup the data, destroy the pool, make a new one and transfer everything back.

 

[danb35]

ZFS is not fragile. All filesystems have a risk of data loss/corruption if the power fails at an inopportune time, and the risk with ZFS is less than most due to the way the filesystem is designed. Nonetheless, the risk is non-zero. The same is true of the issue with ECC RAM--all filesystems are vulnerable to bad RAM, and ZFS isn't uniquely so, but since ZFS is otherwise so robust you'd want to use ECC to maximize that robustness. Filesystem recovery tools aren't separately available for ZFS; they're integrated into the filesystem itself with scrubs and the like.

You've set up a pool in which the loss of any single disk will result in the loss of all your data. To gain redundancy, you can set up a new RAIDZ pool and copy/restore the data to the new pool. If you had a single disk, rather than a three-disk stripe, you could add a second disk as a mirror--I don't think that's possible with your present configuration, but it might be worth checking out before you make any major changes.

 

[Ericloewe]

ZFS is not fragile. All filesystems have a risk of data loss/corruption if the power fails at an inopportune time, and the risk with ZFS is less than most due to the way the filesystem is designed. Nonetheless, the risk is non-zero. The same is true of the issue with ECC RAM--all filesystems are vulnerable to bad RAM, and ZFS isn't uniquely so, but since ZFS is otherwise so robust you'd want to use ECC to maximize that robustness. Filesystem recovery tools aren't separately available for ZFS; they're integrated into the filesystem itself with scrubs and the like.

You've set up a pool in which the loss of any single disk will result in the loss of all your data. To gain redundancy, you can set up a new RAIDZ pool and copy/restore the data to the new pool. If you had a single disk, rather than a three-disk stripe, you could add a second disk as a mirror--I don't think that's possible with your present configuration, but it might be worth checking out before you make any major changes.

It should be possible to add mirrors to each disk individually.

 

[camilo suarez]

if you are afraid of power outages, just buy a UPS and set the server to shut down when the UPS is in battery mode or in critial level. and you will not give a chance to loss information because of power loss.

 

[danb35]

The OP has a UPS, though he(?) apparently didn't buy one that could communicate with the server to shut it down under low power conditions.

 

[nasnice]

Sorry for the late reply, am travelling...

Yes it is he and I do have an APC Smart Ups 1000. I do not think, will verify when back in Portugal, that it has an interface for signalling.

It looks like I am in for some big data transfers... Just to be clear I will end up with 6 3Tb drives in Raidz2 but 3 of them will be used for backing up the data first. So I need to use at least 3 other drives (have some 1TB drives spare) and later change the 1TB drives one by one for the then empty 3Tb Drives correct?

Is this a straightforward process or do I need some special skills? Is there a howto on this subject? Did not have time to seek the forum just yet this week is very busy...

 

[Ericloewe]

Sorry for the late reply, am travelling...

Yes it is he and I do have an APC Smart Ups 1000. I do not think, will verify when back in Portugal, that it has an interface for signalling.

It looks like I am in for some big data transfers... Just to be clear I will end up with 6 3Tb drives in Raidz2 but 3 of them will be used for backing up the data first. So I need to use at least 3 other drives (have some 1TB drives spare) and later change the 1TB drives one by one for the then empty 3Tb Drives correct?

Is this a straightforward process or do I need some special skills? Is there a howto on this subject? Did not have time to seek the forum just yet this week is very busy...

Just follow the manual's process for replacing drives.

 

[nasnice]

Hi All,

Just finished transferring the Data back to the Win 7 Sever that has two 3TB drives and one 1 TB drive.

The Nas is empty now so I think I will start from scratch with the latest version of Freenas.

Unfortunately I had to use two of my 3 TB drives to empty the Nas. So I am in a difficult spot and need some advice...

At the Moment I have four 3TB drives two 120 GB drives and two 1 TB drives available for building the new Nas. After the data is transferred back to the new Nas, the plan is to install the then empty 3TB drives curently in the Win 7 server also to the Nas so the final configuration would be six times 3 TB.... in a RAidz2 configuration.

What is the best plan of attack? Regarding Drives / Vdevs / Mounts .... Read a lot but cannot find a clear answer...

If I use the two 1 TB drives in a six drive Raidz2 config will this limit the other 4 drives to 1 TB as well? So I will end up with only 4 TB of usable space on the Nas initially?

Also there is an USB port on my Smart UPS... If I connect that to he Nas will freenas do the rest? Monitor and shutdown etc or do I need additional Soft?

Any help is much appreciated!
Thanks in advance.

 

[cyberjock]

To answer your question regarding pool configuration the FreeNAS manual and my noobie guide answers your question.

For UPS setup the FreeNAS documentation again provides instructions.

 

[nasnice]

Hi Cyberjock!

Thanks for your helpful reply!

I've seen more of this kind of reply's even to the point of defaming a Nas instructor who rightfully stated that reading a 280 page manual is NOT the sensible thing to do but forums like this one might provide users with much faster and friendlier support.

I was hoping for some experienced insights because in all honesty I have tried RTFM but find it a very confusing utterly unreadable piece of technical work using lots of abbreviations with links all over the place that end you up very far from the answer that you were looking for.... Just one example:

The installation chapter has much more info on virtualisation than on an actual dedicated installation....

To my best belief my specific questions on the ZFS Config are NOT covered in the Manual neither in the Noobie guide....
My question if my APC smart UPS can work with Freenas is also not answered.... Yes Freenas caters for some UPS's but I fail to find a list of supported hardware models....

Anyone?

 

[gpsguy]

Yes, that is correct, although due to the way drives are sold versus how they are used (1000 vs 1024), the usable space will be closer to ~3.6Tb.

Once you've been able to free up the other 3Tb drives in your Win 7 box, you can start replacing the 1Tb drives in your server. Follow the instructions in the manual to replace a drive and wait for it to resilver. Once, the first one is done, rinse and repeat for the other one.

After the second one finishes resilvering, FreeNAS should have autoexpanded the storage, giving you about ~10.8Tb in total.

Please read section 6.3.13 of the manual "Replacing Drives to Grow a ZFS Pool" to ensure that the autoexpand property is on.

If I use the two 1 TB drives in a six drive Raidz2 config will this limit the other 4 drives to 1 TB as well? So I will end up with only 4 TB of usable space on the Nas initially?

 

[nasnice]

Yes, that is correct, although due to the way drives are sold versus how they are used (1000 vs 1024), the usable space will be closer to ~3.6Tb.

Once you've been able to free up the other 3Tb drives in your Win 7 box, you can start replacing the 1Tb drives in your server. Follow the instructions in the manual to replace a drive and wait for it to resilver. Once, the first one is done, rinse and repeat for the other one.

After the second one finishes resilvering, FreeNAS should have autoexpanded the storage, giving you about ~10.8Tb in total.

Please read section 6.3.13 of the manual "Replacing Drives to Grow a ZFS Pool" to ensure that the autoexpand property is on.

Thanks gpsguy,

This confirms my initial ideas... Would it then not be more feasable to start the Raidz2 with four disks of 3 TB and after the data transfer install the two other 3 TB drives in the Nas and EXTEND the ZFS Volume by adding the disks?

TIA

 

[gpsguy]

See section 8.14 of the manual, to configure your UPS. Your APC Smart UPS should be supported. In the manual, there's a link to the "supported UPS devices" - http://www.networkupstools.org/stable-hcl.html

Also there is an USB port on my Smart UPS... If I connect that to he Nas will freenas do the rest? Monitor and shutdown etc or do I need additional Soft?

I keep the PDF version of the manual on my Windows desktop, so I can easily search it for keywords.

 

[gpsguy]

No. You can't add the other 2 drives into the original vdev after the fact.

If you wanted to keep RAIDz2 for your extended volume, you'd need to add 4 more disks. IFF you mirrored the 2x3Tb drives and used them to extend your volume, you'd still have some fault tolerance, but not as much as you'd have with a single 6 drive RAIDz2 volume. With the latter, you could loose any 2 drives and still have protection. If you mix RAIDz2 and a mirror and both drives in the mirror failed, you'd loose your volume. Plus, you have 3 drives of overhead vs 2, giving you less space on the volume.

Would it then not be more feasable to start the Raidz2 with four disks of 3 TB and after the data transfer install the two other 3 TB drives in the Nas and EXTEND the ZFS Volume by adding the disks?

 

[no_connection]

The manual have enough info to be confusing but not enough to be useful in many cases. Or at least when I needed it.
http://doc.freenas.org/index.php/Main_Page
Is a little easier to search at times, and usually up to date.

A compatibility list for UPS are linked to in the manual page 214.
http://www.networkupstools.org/stable-hcl.html

You need to set up the NAS with all the drives you want to use when doing Z2. You can't add the two extra drives later.

You can create the four disks as two vdevs with mirrored disks that then are striped across the pool. Then you can add the two remaining disks to a vded as a mirror. That will stripe it to the pool as well.

CJ do explain it a bit better than me what you can and can not do in the slides though.

You should have a backup anyway, so you might as well buy two new disks and set up a 6 drive Z2 from the beginning. Then use the two 3TB drives as backup.
Cheaping out now will only bite you back at a later stage.

 

[danb35]

I remember that thread. The instructor was not in any way defamed, and she also was not in any way right.

The folks who answer questions here are volunteers, with the exception of the iX employees who occasionally post. We do so for a variety of reasons, but a common trait we all share is that we don't get paid to do it. It is disrespectful of our time to demand to be spoon-fed answers that are contained in obvious locations like the manual, FAQs, sticky threads, etc. I understand that 280 pages of manual is a lot (but then what? Should information be removed to make it shorter?), but there's a marvelous invention called a "Table of Contents" that can direct you much more specifically to the relevant parts of the manual. There's no need to read it cover-to-cover, unless you really want to.

To your question, yes, a RAIDZ2 vdev consisting of 4 x 3 TB disks and 2 x 1 TB disks will have a net capacity of about 4 TB, less filesystem overhead and GB/GiB conversion. Once you replace both of the 1 TB disks with 3 TB disks following the instructions in the manual, its capacity will increase to about 12 TB.

Regarding the UPS, no, it is not simply plug-and-play. Section 8.14 of the manual describes how to set it up, and links to the list of supported models at http://www.networkupstools.org/stable-hcl.html. From that list, you can filter by manufacturer and model to see if your UPS (which you still haven't specified, though at least in your last post you've given some information about it) is supported, and if so by which driver.

 

[nasnice]

Hi Danb35,

First of all Thank you for your reply... Please note that I did not attack anyone... just mildly protested at being HARSLEY directed in a direction that I already explored (given my initial ideas..) All I did was ask for confirmation or wiser options from experienced users... Please read the following intresting text and the comments on TFM of Freenas (Frustation) to understand my insecurity... Completely agree with the author BTW...

http://arstechnica.com/information-...as-distribution-shootout-freenas-vs-nas4free/

IMHO Cyberjock likes to police a little to much as I tried to prove with the example. I apreciate the many forums I subscribe and contribute to VERY much because normally they are a priceless source of information that sometimes is much better and friendlier than TFM... Remember Forums also have a social aspect which sometimes gets completely neglected by Die Hards on the subject.

On the Actual questions I am very confused because I initially started my first freenas with a single 3TB disk and coud extend that with another 3 Tb drive from the ZFS managment dialog, chose a stripe configuration and even after that I could extend that extended volume with another 3 TB disk in exactly the same fashion... Is this (stripe option) maybe the exception to the rule? I am sure that that answer is not in any manual.

On the UPS I did find the UPS chapter in the manual (use the web form http://web.freenas.org/images/resources/freenas9.2.1/freenas9.2.1_guide.pdf) But did not click on external links since they do not open in a new window but in the actual window that one is reading thus further complicating the readability of TFM. I did mention that I had an APC Smart UPS, that to my surprise and delight does have an USB interface. Read in the NUT pages that a driver is availabe... but does Freenas load that driver automatically in the drop down menu or do I manually need to add that driver and if so how...

Remember I am a newbie to Freenas and FreeBSD.... but not to Forums...

 

[gpsguy]

Yes, you can stripe vdevs to extend your volume. A vdev could be as small as a single drive or contain multiple drives in mirror, RAIDz1, ... configurations.

Striping single drive vdev's results in a pool without any redundancy. If any one of the drives fail, all your data is gone.

That's why I (and other's) said that if you were to start with a 4 drive RAIDz2 volume and wanted to extend with the other 2 - 3Tb drives, we'd suggest you mirror them and stripe in that set of mirrored drives. But, the best solution, would be build the RAIDz2 volume with 6 drives from the start.

In the Actual questions I am very confused because I initially started my first freenas with a single 3TB disk and coud extend that with another 3 Tb drive from the ZFS managment dialog, chose a stripe configuration and even after that I could extend that extended volume with another 3 TB disk in exactly the same fashion... Is this (stripe option) maybe the exception to the rule?

 

[gpsguy]

As I said earlier, it appears that your UPS is supported. It's just a matter of selecting the driver from a drop down list. On the NUT page, there are 2 "Smart-UPS" entries, using different drivers. Rather than guess, I listed that information for you.

Smart-UPS USB usbhid-ups
Smart-UPS apcsmart

Read in the NUT pages that a driver is availabe... but does Freenas load that driver automatically in the drop down menu or do I manually need to add that driver and if so how...