Jump to content
  • 0

Pretty-boring Usage Question


Wearyeyed
 Share

Question

Okay, so I have used and loved DP and Scanner for as long as WHSv1 existed, and I continue to use them on my Server 2012 r2 machine.

 

It acts as a file server, "my documents" location, and machine back-ups location for our client machines in the house, making client restores\rebuilds super-easy, and accessing all of our "common files" a breeze across machines.

 

I use Crash Plan and love the way they all play together, both in theory and in practice - oh, yes, I have made more than my fair-share of "recovery scenarios" come to life over the years.

 

But, I am boring in my execution...I have 4 drives, and they are duplicated x4, so I essentially end-up with some semblance of a 4-drive RAID 0 configuration.

 

Mainly so if I die in a fiery car wreck, wifey can trip over the drive cage, take any random drive that falls out and have a friend set-it up on her local machine and life goes on without my techy-overhead.

 

Here's the situation and question: In the event of a single drive failure, the pool goes into read-only.

 

It *seems* like to get anything up and running quickly for normal use (say, for example, a Quicken file to which I will need to write) until a replacement drive is available, I would need to:

  1. Turn duplication back to 3 (instead of 4)
  2. Remove the bad drive

Otherwise, DP get's busy trying to make the 4th copy across the remaining three drives, and creates a balancing mess that later causes a bunch of overhead.

 

Am I doing (or thinking about) this wrong?

 

Is there a better way?

Link to comment
Share on other sites

12 answers to this question

Recommended Posts

  • 0

(post moved to the appropriate section).

 

Well, to address the initial question,  just remove the bad drive.  StableBit DrivePool will handle things from there.  If there aren't enough disks to get back to the proper level of duplication, it will warn you.  But reducing the duplication level isn't necessary. 

 

 

As for a "hot spare", this really isn't needed. Once the missing/failed drive is removed, StableBit DrivePool will take care of reduplicating the data.  Additionally, the StableBit Scanner balancer will "effectively" do this, by evacuating the contents of the drive, if it detects unreadable sectors. 

 

Between these two things, there really shouldn't be a need for hot spares, as .... it should treat the entire rest of the pool as "hot spares". 

 

If you want it to work more aggressively, enable evacuation for SMART warnings, as well. 

 

 

 

I have only experienced the read only when a drive completely failed which resulted in it been flagged as missing in drivepool which put the pool in read only which is ok I suppose it's kind of a safe mode the only way to get out of this is remove the failed drive from the pool Chris may have another way

 

Yeah, this happens so that if the issue is just a bumped USB cable or the like, the data won't get out of sync.  

Link to comment
Share on other sites

  • 0

I have been wondering about similar scenarios. If you use scanner and use the Scanner balancer in DP (which is used by default), then I would think that if you have 4 HDDs and only use x3 duplication, it would never go into read-only mode for long with a 1-HDD failure (not sure though), just until the 1 defect HDD is evacuated. Similarly, using x2 duplication would make a 4 HDD Pool (with just 1 HDD of net unduplicated content) rather resilient.

 

But yes, recovery in another machine would require the friend to access all HDDs.

 

I never requested, but have considered to, DP to allow to designate spare HDDs or hot-standbys to replace failed HDDs on the spot.

Link to comment
Share on other sites

  • 0

Hi umfriend

 

A hot spare has been asked about before in fact must be a few years now and I believe I may well be wrong but it was deemed not necessary I think it would be good too. I would also like to know how things stand with all the suggestions that have been made in the past relating to products updates from what I understand from Alex's last post drivepool won't be changing much if at all. Even if they ended up been addon products I wouldn't mind there's just not much mention of anything at the moment.

Link to comment
Share on other sites

  • 0

Hi Lee,

 

I can actually see why one would think for it not to be necessary as long as there is enough space left on HDDs remaining in the Pool. It shouldn't be very useful IMHO. But in the specific cases of the OP (and in my case where I force Pools to store one copy on each HDD in the Pool) it might be helpful. I am still on the fence on this one. In my case, for instance, it is driven by the desire to use Server Backup for the entire server.

Link to comment
Share on other sites

  • 0

The main problem I have found is if a drive completely fails it is classed as missing in drivepool this results in the pool becoming read only this is ok if you are near the server but as I found while on holiday there's not much can be done until you get home in theory a hotswap drive would stop this. it would be possible to log in remotely and delete the missing drive from the pool which should fix the read only issue but if you don't have enough free space to re-duplicate I would imagine that would cause another problem.

Link to comment
Share on other sites

  • 0

Yes (and sorry OP for hijacking) Lee, but the thing is, if the hot-standby would allow to reduplicate, then it would also be possible had the hot-standby HDD already been part of the Pool...

 

My thinking was more that you could have one hot-standby HDD to cover for the first HDD to fail in *any* number of Pools. But then again, aside from hierarchic Pools, there is no real reason to have many Pools I think (although, in my case, 2 HDDs go to standby often and for long periods as they are only used for client backups).

Link to comment
Share on other sites

  • 0

Indeed it's not going to happen anyway so it's all speculative but having a pool stuck in read only is a pain everything fails backups, databases , client's trying update there files basically anything that writes to the pool stops. In theory a hotswap would kick in once a missing/failed drive occurs and solve this of course this can be all done manually just leave an empty drive connected at all times remote in add the new drive remove the old drive and it's fixed albeit it's a bit of faffing around even more so when your 3000miles away

Link to comment
Share on other sites

  • 0

I have only experienced the read only when a drive completely failed which resulted in it been flagged as missing in drivepool which put the pool in read only which is ok I suppose it's kind of a safe mode the only way to get out of this is remove the failed drive from the pool Chris may have another way

Link to comment
Share on other sites

  • 0

Well, to address the initial question,  just remove the bad drive.  StableBit DrivePool will handle things from there.  If there aren't enough disks to get back to the proper level of duplication, it will warn you.  But reducing the duplication level isn't necessary. 

 

 

Thank you for that, Drashna!

 

I love tinkering with these two products and have for a long time in many different configurations and for many different needs, as my household grew.

 

Maybe I needed to start a post just to tell you that.  ;)

 

You and Alex keep up the good work!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Answer this question...

×   Pasted as rich text.   Paste as plain text instead

  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.

Loading...
 Share

×
×
  • Create New...