Ability to Pre-Clear Drives beyond Your Max Number of Attached Devices

[EternalFootman]

So, this is pretty simple, but I'm not sure how well it will be received...  I have Unraid Plus, and I have two parity drives and 10 data drives.  One drive failed, and I didn't have a spare, so I had to wait to order a new drive before I could rebuild the array.  My fault, I know.  So I got a great deal on two 3TB drives hooked one up in the place of the bad drive, pre-cleared it and rebuilt the drive.  Went to hook up the other drive to pre-clear it and get it ready in case another drive went bad so that I could quickly swap it in.  However, I wasn't able to do that, because the array stopped all services because I had 13 drives physically connected to the computer, despite the fact that I only had 12 drives assigned.

So here's my request - could you set the maximum number of devices to the "assigned category", so that someone like me could pre-clear another drive and get it ready to be a quick spare? Does that make sense? I'm not trying to cheat the system, just trying to get my array ready for failures and have as little down-time as possible.

[itimpi]

You do realise that it is not necessary to pre-clear drives before using them to replace a failed drive?    The rebuild process overwrites the existing contents anyway.     The only purpose of a pre-clear in such a scenario is to act as an initial stress test of the drive.

[JonathanM]

Also, the attached devices is only checked at start of array. You are free to connect other devices after the array is started, and as long as they are disconnected when you need to start the array, you will be fine.

 

So, just make sure any extra devices are powered down on array start, and you can hot plug extra drives into your hot swap bays any time you want.

 

Or, upgrade your license if you wish to keep the devices connected at array start.

[EternalFootman]

Yes, I do realize that you don't have to pre-clear.  But I also believe that it is an excellent idea, and I like to do it.

I did not, however, know that I could connect a device after the array is started and that it wouldn't interrupt the array's operation. I guess I just figured that if it stopped the array upon startup that it would stop the array if you hot-plugged a new drive in. I'll have to try that and see what happens.

 

I do not, however, think that spending another $50 on this software, as good as it is, just for the ability to pre-clear disks is the right answer.  I figured that someone would say that - it was just a matter of time, of course. What I've asked for is - in my mind - a legitimate request to help make a happy customer even happier. It provides UnRaid customers with better service, keeping to "the spirit of the law", so to speak, but giving customers a little bit of added flexibility to taking care of their arrays. Conversely, I see the need/practicality in having different "levels" of functionality at different prices. If the creators of UnRaid see it the way you do, then fine, but making happy customers keeps happy customers, right?  I, of course, think it a legitimate request that makes a customer's life easier, but doesn't really warrant the need to move up a level like that.  I guess we'll see if they do.

Edited April 9, 2019 by EternalFootman

[itimpi]

I see where you re coming from but I do not see Limetech being changing their licensing model any time in the near future.

 

It is worth pointing out that you can always do the 'stress test' part of pre-clear on another system using the standard tools provided by the disk manufacturer.  It does not need to be done on your Unraid system.

 

Another way to handle your problem is to have a USB SATA dock that you plug into the Unraid system.   This makes it easy to plug in a drive after the array has been started even if you do not have hot-plug SATA capability on your system.   If going this route it is worth checking what dock you get as not all USB docks seem to support reading the SMART attributes and being able to do so is a good idea.  Having such a dock is a good idea anyway as it provides a convenient way of taking backups of your data or mounting disks temporarily for any reason.   I have Pro licenses so do not ever hit the attached devices limit but I still find that having such a dock on my Unraid system is something I would normally recommend.

Edited April 9, 2019 by itimpi

[kizer]

Exactly what I use. I have a USB dock handy so I can swap out drives using Unassigned.Devices plugin.

I've always used another machine with a Trial License so I could run it for several days and not stress out my Server since well if your into Machine Building you can always scrape up parts to make something work. lol

 

Even on my current setup I have a USB drive for monthly backups I could just unplug and reconnect another  do my preclear and then plug it back in.

 

Speaking of Spares I need to buy a spare just incase too.

[EternalFootman]

I do actually have a nice USB dock that is attached to my editing desktop.  I'll have to try that as well - That actually seems like the best work-around, and would keep me from having to "install" the new spare into my tower just to pre-clear it.  

I also want to say that I'm not asking them to change their license, just change the way they count the drives. Guess whether or not that is changing the license is semantics, but most of you have all given my some great advice, so thank you very much!