Re: [gentoo-user] NAS and replacing with larger drives

[Dale]

Mark Knecht wrote:
>
>
> On Sat, Dec 17, 2022 at 12:10 PM Wol <antlists@××××××××××××.uk
> <mailto:antlists@××××××××××××.uk>> wrote:
> <SNIP>
> > Do you want the system layered, with each layer doing one job? Use
> > dm-integrity to protect against corruption, raid to join the disks, lvm
> > to partition them, and ext to manage the directories and files.
> >
> > I do the latter ...
>
> No argument there, at least on a group of drives where you 
> want to have flexibility in the future. Desktop computers or
> system drives certainly. You didn't tell me what replaces
> the compression aspect of the problem but I'm sure there's
> something. It's a great strategy if you have the expertise and
> time to set it up and then manage it when a problem arises,
> if it ever arises. 
>
> I'm just asking what's the purpose of doing LVM, or your
> suggested layering, specifically on a storage pool for a 
> home user like Dale? That's the part I don't understand, 
> especially for a new NAS user like Dale?
>
> Mark
>
>
>

My reasoning is simple, I'm already familiar with LVM and how to manage
it.  While I swap drives on my Gentoo rig pretty regular lately, I don't
want to be limited from doing that on a NAS either.  If for example I
want to replace a 10TB drive with a 16TB drive, LVM makes that easy and
I know how to do it already.  With ZFS tho, is that even doable and if
it is, do I want to learn to do it with a new tool?  From what I've
seen, I'm not even sure you can do that.  It seems you can expand by
adding a drive but not replace or shrink. 

As a example.  I went back to a basic pool of two drives.  I then
recreated a dataset, or whatever it is called, and added for it to be
encrypted.  Since I did that, I get write errors.  I can mount it just
fine but that's it.  I have no idea what the cause is, google isn't
helping and to be honest, I'm thinking about target practice for the
thing.  It took me a good long while to set up the most basic thing. 
Adding encryption shouldn't be hard but apparently, it is more difficult
than I thought.  That or its so secure even I can't use it even with the
password.  lol 

This is what I like about LVM and cryptsetup.  I create a partition, or
use a whole drive, as needed.  I use cryptsetup to start the process
with one drive.  I then put ext4 on top of that.  Then I add a second
drive to that pv, add that to the volume group, extend the file system,
all done.  And it is encrypted as well.  If I need to move from one
drive to say a larger drive, no problem.  Add drive, move data, remove
old drive, extend file system if needed, all done.  I have notes but
I've done it a lot recently and have the general idea still glued to the
back of my head.  ;-)  Thing is, ZFS isn't making sense to me so I'm
clueless where to start when something goes wrong or even getting it to
work period.  I may try watching a video on ZFS and see if that helps. 
Maybe it will, maybe I'll still prefer LVM.  After all, I'm a old dog. 
New tricks ain't easy.  ROFL 

If I bought a pre-made NAS, I'd just have to deal with it.  I'd keep
hammering until I got it to where I could backup my data.  If I build a
Raspberry thing, NAS software may not be my first choice.  Maybe, just
maybe, my light bulb will pop on and I can make sense of TrueNAS and
ZFS.  If so, fine.  Right now, it's a lot of work with really no gain. 
I'm not able to backup my data yet.  It's a brick, time consuming and
confusing brick at that. 

After supper, I'm rebooting and see if I can beat some sense into
again.  Seriously considering using dd and starting over from scratch. 
I can't figure out how to do that with the GUI thing.  No delete button,
that I can find anyway. 

Dale

:-)  :-)