Help With Volume creation TS-251+

[Snowpow]

Hello Everyone ,
I am trying to figure out what volume option to go with in my situation and how much space to allocate.
I have just bought TS -251+ with two 6TB drives. Currently still synchronizing to Raid -1 pool.
As you can see out of 6TB available storage I am left with 5.33TB
In fact it says that total size is 5.45TB. Out of which 122.36GB Used I am assuming by NAS software and system files. Is that correct ? That seems quiet a lot!
On the other hand Where did other 0.55TB (550GB) go?
That is more than the whole drive size of my laptop.


First of all do you recommend using snapshots ?
If so, should I go with recommended 20% guaranteed storage pool capacity for snapshots and create thick or thin volume for other 80%? Which( thick or thin) one would you recommend?
I am looking to have 2 different MacBooks( 2 users) (500GB) to backup via time machine. And have other folders to store photo and video files along with documents.
With either of these options Will I be able to later add a dedicated folder to be used for CCTV camera ? Or I will need a dedicated (volume)partition for that?

[dolbyman]

you are aware that harddrives never have the usable size they are advertised with .. right?
https://www.seagate.com/support/kb/why- ... -172191en/

do one thick volume..and if you need snapshots ..size the volune a accordingly..no need for complex volumes on a small unit like this

[storageman]

you are aware that harddrives never have the usable size they are advertised with .. right?
https://www.seagate.com/support/kb/why- ... -172191en/

do one thick volume..and if you need snapshots ..size the volune a accordingly..no need for complex volumes on a small unit like this

Actually they are the exact size they are advertised, it is just people don't understand what a megabyte is

[Snowpow]

you are aware that harddrives never have the usable size they are advertised with .. right?
https://www.seagate.com/support/kb/why- ... -172191en/

do one thick volume..and if you need snapshots ..size the volune a accordingly..no need for complex volumes on a small unit like this

Thank you for explaining this .
I guess In this case the 120 GB is used by the NAS system . Correct?
Do you recommend using snapshots for my situation ? If so is 20% that is recommended seems to be reasonable ? Wouldn’t thin volume be more flexible in that case? -if let’s say my snapshots will be using only 5% , then I will have extra 15 % of unused storage with thick volume. ?

[dolbyman]

I think for snapshots a thin volume works actully better

up to you if you want to use snapshots..don't forget backups (external)

[Snowpow]

Thank you, I guess I will go with one thin volume but reserve the 20% to snapshots.

[dolbyman]

@storageman i know..but I let that link explain..less to write for me

Actually they are the exact size they are advertised, it is just people don't understand what a megabyte is

[Snowpow]

I was trying to find more information on the subject and then found this, which almost identically mirrors my situation, but this question never got any replies:
Can you guys help me to decide how to allocate volumes assuming my usage will be the same? Do snapshots actually worth it? I would rather use one single volume with multiple folders.


Hi all,
I'm a newbie in NAS technology and I'm in struggling with some of terms and decisions. I'm like a foreign in this world
I've bought a TS-251 and I equipped it with 2x3TB WD-RED
Further, I expanded the RAM with 2x4GB DDR3L for an amount of 8GB.

I need of redundancy, so RAID-1 is the basic choice.

During the installation phase the system ask to me what kind of archive method to use:
a) Single static volume
b) Multiple Thick Volume with storage pool
c) Multiple Thin Volume with storage pool

I don't understand clearly what are the difference between them and what I can do in the future.
In the future, probably, I'll need to change disk with biggest ones, or add user, nothing else.

Which of the choices offered, it is the best for my needs?
What is a storage pool (with simple words, please)? What can I do with it?

Actually, my network is composed by devices and 3 users:
- 1 WIN station with 3 independent users (me + 2 other users)
- 2 MAC stations with one user for each (me in both devices)
- Smartphones and TV
- IP WebCam

I would use the NAS for:
1) BACKUP device, for 3 stations (2 MAC + 1 WIN). Every stations must be enable to have owner backup
2) SHARABLE folders device: all users can have access to it.
3) PRIVATE folders device for each (3) user. Every user can access only to its account on the NAS
4) Private Cloud
5) Video surveillance with IP-Camera
4) watch TV using shareable folders (videos and images)
5) Backup for the smartphones (if possible) instead to use the public clouds (iCloud, etc )

[storageman]

The pool is the whole thing, the whole amount of space.
The pool can contain one or more volumes
In your situation go with one thick volume but leave some space in the pool for QVR Pro if you intend to use this.
Keep things simple!

Some stuff here
https://www.qnap.com/en/how-to/knowledg ... ck-volume/

[P3R]

I think for snapshots a thin volume works actully better

I don't understand that so I have to ask why you think so?

[dolbyman]

I remember a discussion that thick volumes were wasting space on snapshots..thin volumes (with reclaim schedule) were better

afaik it was storageman that had more info about it

but the argument was that thick volumes already occupy the full space on the pool leaving only the reserved space for snapshots

thin volumes also let you use the provisioned space for snapshots (and snapshots work on block and not file level)

I will try to find the thread

[dolbyman]

to put action to where my mouth is, I am testing it right now on my testing machine (TS-853BU)

a 18TB thick volume (~1TB used) and 3TB free pool space (no guaranteed snapshot space needed.. due to thick volume)... setup a daily snapshot routine .. let's see how that goes

[P3R]

but the argument was that thick volumes already occupy the full space on the pool leaving only the reserved space for snapshots

Thick volumes occupy the space they're configured for so the issue with them is of course if the administrator have the bad habit of immediately setting them to the maximum possible size even if just needing a fraction of the storage. Thick volumes can be converted back and forth to thin if necessary, which maybe can be used to do a space reclaim if having made the mistake of using up all space?

Thin volumes are more complicated to understand, especially for the many newcomers that struggle already with the storage pool concept. In my opinion thin volumes are exactly like iSCSI, those that are unsure and need to ask about if to use them shouldn't be using them. The users that really need them already know that.

My recommendation for those that ask is to use thick volumes but only configure the volume to the expected usage within 6-12 months (including a safety margin of say 20-40 %). Thick volumes are easier to grasp than thin while still not sacrificing any of features that may in the future become interesting, like static volumes do. Thick volume performance is in between static and thin but very, very few really need the small additional speed of static volumes.

I'm using thick volumes with snapshots and have no problems with it.

[scolumbo]

I thought this thread implied snapshots with thick volumes are not typically recommended:

viewtopic.php?f=25&t=143592





Edit: In particular, this post:

viewtopic.php?p=685709#p685709

[P3R]

Edit: In particular, this post:

viewtopic.php?p=685709#p685709

Well I'm not in agreement with that recommendation from a Qnap representative because, as storageman says in the post that follows, "thin volumes have other problems".

Obviously you need to have enough free space in the pool for a complete snapshot. I'd rather say that snapshots are not really usable when, as so many home users, you want to use up very much (>80 %) of your storage.

Yes a thin volume will use the storage more effectively with snapshots but I still don't think it's a good recommendation for someone that haven't understood the thin volume concept. One can't always give recommendations based on what's the optimal solution, you also have to consider the level of experience of the person asking so that they're given a recommendation that they can understand, administer and live with. Thick volumes and reserved snapshot space are easier to understand for new NAS users as then the limits for each storage type are clearly defined. These users will still have the option convert to a thin volume when they feel ready to swim in the deep water.