Re: Linux supprt (was: Hardware for a back up server? [WAS Re: How to use dmsetuup?])

[Larry Martell]

On Mon, Nov 13, 2023 at 7:48 AM Stefan Monnier  wrote:
>
> >> Indeed, technically-inclined people are often better served with Free
> >> Software, and Free Software can also be a great choice for large
> >> corporations who can either have on-site techsupport people or can hire
> >> external support, but it is a lot more difficult to find commercial
> >> support for merely non-techie user.  This is mostly the domain of
> >> proprietary software :-(
> >
> > The way out of this is having strong local user groups, which is,
> > of course, easier in densely populated areas.
>
> I think this still only covers a small fraction of the problem.
> It just lowers the bar of the "technically-inclined" limit.
> I think many more people just want to have someone they can call on
> the phone to help them get through their yearly technical problem.

In my experience I get much better support from the user community of
an open source product then I get from paid support of a commercial
product. Frequently I know more about the product than the person I am
dealing with.

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Stefan Monnier]

Anssi Saari [2023-11-13 12:34:13] wrote:
> Stefan Monnier  writes:
>> My home NAS is in a completely different category:
>> an ARM SBC with on-board SATA.  Much smaller, extremely quiet (no fan),
>> and between 5W and 10W of power consumption depending on whether it's
>> mostly idle (the overwhelmingly common case) or not.
> So which ARM SBC and does it run stock Debian? And how many SATA ports?

In my case, I'm currently using a BananaPi at one place and at the other
I upgraded to an ODroid-M1.  In both cases there's only a single SATA
port (tho the ODroid has an nvme-M2 port as well which I'm not
currently using).  The ODroid-M1 is the main "backup server" and the
other holds my backup's backup.

Both run stock Debian stable (in both cases the installation was
manual/tricky rather than via debian-installer :-( ).

None of the services they provide are sufficiently important to require
something like RAID, which makes things easier.

And yes, I've had problems with the BananaPi's power supply (I had to
try various power blocks *and* cables until finding ones good enough
for reliable operation :-( ).
The ODroid's power supply seems significantly better in this respect.


Stefan

Linux supprt (was: Hardware for a back up server? [WAS Re: How to use dmsetuup?])

[Stefan Monnier]

>> Indeed, technically-inclined people are often better served with Free
>> Software, and Free Software can also be a great choice for large
>> corporations who can either have on-site techsupport people or can hire
>> external support, but it is a lot more difficult to find commercial
>> support for merely non-techie user.  This is mostly the domain of
>> proprietary software :-(
>
> The way out of this is having strong local user groups, which is,
> of course, easier in densely populated areas.

I think this still only covers a small fraction of the problem.
It just lowers the bar of the "technically-inclined" limit.
I think many more people just want to have someone they can call on
the phone to help them get through their yearly technical problem.


Stefan

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Anssi Saari]

Stefan Monnier  writes:

> My home NAS is in a completely different category:
> an ARM SBC with on-board SATA.  Much smaller, extremely quiet (no fan),
> and between 5W and 10W of power consumption depending on whether it's
> mostly idle (the overwhelmingly common case) or not.

So which ARM SBC and does it run stock Debian? And how many SATA ports?

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[tomas]

On Sun, Nov 12, 2023 at 03:17:17PM -0500, Stefan Monnier wrote:
> > FOSS is great for learning by doing, but commercial products can be a better
> > choice when a family member, a friend, a neighbor, and especially clients
> > and employers, want a computer, a server, a network gateway, etc..  It is
> > ironically satisfying when those commercial products have FOSS on the
> > inside.  :-)
> 
> Indeed, technically-inclined people are often better served with Free
> Software, and Free Software can also be a great choice for large
> corporations who can either have on-site techsupport people or can hire
> external support, but it is a lot more difficult to find commercial
> support for merely non-techie user.  This is mostly the domain of
> proprietary software :-(

The way out of this is having strong local user groups, which is,
of course, easier in densely populated areas.

In Berlin, e.g., there were several linux user groups which had
"open days" (some even once a week) where people went with their
hardware and got it fixed. And got to know nice people. Often
at no cost.

In the smaller city I live now there is at least one such place.

Support your local free software support group :-)

Cheers
-- 
t


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Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Stefan Monnier]

> FOSS is great for learning by doing, but commercial products can be a better
> choice when a family member, a friend, a neighbor, and especially clients
> and employers, want a computer, a server, a network gateway, etc..  It is
> ironically satisfying when those commercial products have FOSS on the
> inside.  :-)

Indeed, technically-inclined people are often better served with Free
Software, and Free Software can also be a great choice for large
corporations who can either have on-site techsupport people or can hire
external support, but it is a lot more difficult to find commercial
support for merely non-techie user.  This is mostly the domain of
proprietary software :-(


Stefan

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[David Christensen]

On 11/12/23 09:15, Andrew M.A. Cater wrote:

On Sat, Nov 11, 2023 at 04:01:47PM -0800, David Christensen wrote:

An obvious difference between internal and external drives is physical
protection.  Internal drives and cables are protected.  Everything gets
power from the same source (PSU, PCU fed by dual PSU, etc.).  External
drives, cables, and power adapters can be moved, yanked, disconnected,
dropped, kicked, subjected to electrostatic discharge, etc..  There are more
parts to fail and more opportunities for failure with external drives than
with internal drives.


This is what I meant: this is why the devices from QNAP / Synology that
are plug and play NAS are also built this way. The Synology devices
can take lots of added modules, seemingly - it all seems expensive
but these are designed for plugging in  and the whole thing "just working".



FOSS is great for learning by doing, but commercial products can be a 
better choice when a family member, a friend, a neighbor, and especially 
clients and employers, want a computer, a server, a network gateway, 
etc..  It is ironically satisfying when those commercial products have 
FOSS on the inside.  :-)



David

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[David Christensen]

On 11/12/23 05:15, Andy Smith wrote:

On Sat, Nov 11, 2023 at 04:01:47PM -0800, David Christensen wrote:

SSD RAID10 is very impressive when everything else matches.  Backups over a
Gigabit LAN onto SATA III SSD RAID10 does not make sense because Gigabit
Ethernet is rated for 1 Gbps read/ write and a SATA III SSD RAID10 is rated
for 24 Gbps read and 12 Gbps write.  I would put HDD's in the backup server
and put the SSD's in the workstation.


I agree with you when it comes to systems that are used purely for
backups in a style that mimics tape backup, i.e. rare need for
random access, which from what I understand does cover Gene's
situation as Gene is used to using Amanda for backups, which is a
(virtual) tape paradigm.

However, especially in a home setting, people often ask more of "the
server", turning it into something that isn't entirely, or even
primarily, a backup server. If those uses involve random access, SSD
of some kind will be very beneficial.

Also there are quite a few backup technologies that do use random
access a lot. A venerable one often mentioned on this list is
rsnapshot or its basic implementation using rsync. This walks the
entire backup tree at every iteration checking metadata and creating
hardlinks. The period of time spent deciding what to back up and how
often massively exceeds the time spent transferring and writing the
data with these systems. They will also massively benefit from low
latency storage on SSD.

So just as a word of caution -- and I know you know this, David -- I
want to say check how much random access is going on, before
deciding rotational media will cut it.



I think we agree that HDD's are slower for many (most?) backup/ restore 
use-cases.  But, I think the slowness is acceptable for the off-hours, 
once a day backup use-case and for the infrequent file restore use-case 
that I anticipate Gene will perform.




PS I stated this before and I have to say it again though: while
building a dedicated backup system seems like a great idea for
Gene's use case, the practical situation for Gene is that he's
been trying for literal years now to make a very simple RAID10
mdadm work on perfectly serviceable hardware. This should be a
simple task, but it's not gone well for him and this list is
unable to get to the bottom of why (I include myself in that, but
I think it reflects more on communications difficulties than a
shortcoming of Linux mdadm). 



There appears to be consensus to set up one storage device with one 
partition and one ext4 file system, and test the various applications 
for file access issues.  It is up to Gene to decide if, what, where, 
when, and how.




I am at a loss as to why, given
those facts, people are still advising Gene to build an entire
new system out of parts. It makes sense for the use case but not
for the user. I don't think it's supportable. For this user I
would have to still stand by my advice of buying an off-the-shelf
NAS.



I think we agree that everyone needs backups.


It is my impression that most of Gene's eggs are in one basket (the 
computer with the Asus Prime Z370 A II motherboard) and that Amanda has 
been broken for a while (?).  I would celebrate Gene implementing 
working backups by any means on any device and any media.  Again, Gene 
decides.



David

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Andrew M.A. Cater]

On Sat, Nov 11, 2023 at 04:01:47PM -0800, David Christensen wrote:
> On 11/11/23 08:52, Andrew M.A. Cater wrote:
> > On Fri, Nov 10, 2023 at 10:22:07PM -0500, gene heskett wrote:
> > > On 11/10/23 19:46, David Christensen wrote:
> > > > On 11/8/23 02:20, gene heskett wrote:
> > 
> > Are these 2TB SSDs or hard disks? I would counsel very strongly indeed
> > against using any ARM-based single board computer as a RAID device on
> > USB connections - they're just *not* up to it.
> 

This at least partly because the USB devices on, say, a Raspberry Pi
tend to share I/O and resources. On a Pi, USB3 takes away from the 
Ethernet, for example.

> 
> On 11/11/23 09:05, Stefan Monnier wrote:
> > I don't think the issue is whether they're ARM based.
> >
> > The issue is simply how you connect the disks: in my experience, disks
> > connected via USB are simply not quite up to a 24/7 situation,
> > especially if the disk is USB-powered.
> 

Right.
> 
> >
> > I have 4 SSD drives connected to a single RPI4 currently, using a
> > powered USB hub.
> >

SSD significantly different to HDD. 
> 
> 
> On 11/11/23 10:47, Stefan Monnier wrote:
> > Hmm...  so maybe the USB connection is not directly relevant either
> > and the real issue is the power?
> 
> 
> An obvious difference between internal and external drives is physical
> protection.  Internal drives and cables are protected.  Everything gets
> power from the same source (PSU, PCU fed by dual PSU, etc.).  External
> drives, cables, and power adapters can be moved, yanked, disconnected,
> dropped, kicked, subjected to electrostatic discharge, etc..  There are more
> parts to fail and more opportunities for failure with external drives than
> with internal drives.
> 

This is what I meant: this is why the devices from QNAP / Synology that
are plug and play NAS are also built this way. The Synology devices
can take lots of added modules, seemingly - it all seems expensive
but these are designed for plugging in  and the whole thing "just working".

> 
> It is not uncommon for communications establishment to fail with external
> drives.  Similarly, communications re-establishment when the computer and/or
> drive resume from a power saving mode.  Writing and testing this kind of
> software is difficult and you need people with both both CS and EE skills.
> There is an astronomical number of combinations to design and test for.  The
> code runs rarely.  For reliable 24x365 operations, the challenge is
> eliminating everything that can cause communications establishment/
> re-establishment -- operator steps, computer configuration, drive
> configuration, power failures, cooling failures, etc..  If you can find and
> eliminate all of them, a USB external drive can stay connected a very long
> time.
> 

*If* is very much the word, I think.
> 
> 
> I have always liked ATX tower cases with lots of drive bays, both internal
> and external.  Over time, more products have become available with good
> cooling and low noise.  I have not found a major computer manufacturer who
> makes servers with all of those features, so I build my own:
> 
> * Fractal Design Define R5 case
> * 3 @ Fractal Design low-speed 140 mm fans
> * Fractal Design Ion+ 2 Platinum 660 W power supply
> * Intel S1200V3RP motherboard
> * Intel Xeon E3-1200 v3 series processors
> * Dual channel ECC memory
> * LSI 9207-8i HBA with "IT mode" non-RAID firmware
> * Seagate Barracuda and Constellation ES.2 HDD's
> * Intel 520 Series SSD's
> * StarTech 2.5" and 3.5" mobile racks
> * Cable Matters black SATA 6 Gbps cables with locking connectors
> 
> 
> They are not cheap, small, or light, but they perform well, are easy to work
> on, are reasonably quiet, and everything stays cool.  They have plenty of
> capacity for future upgrades.
> 

Nice parts list and good suggestions.
> 
> 
> SSD RAID10 is very impressive when everything else matches.  Backups over a
> Gigabit LAN onto SATA III SSD RAID10 does not make sense because Gigabit
> Ethernet is rated for 1 Gbps read/ write and a SATA III SSD RAID10 is rated
> for 24 Gbps read and 12 Gbps write.  I would put HDD's in the backup server
> and put the SSD's in the workstation.
> 
> 
> David
>

there's no doubt that you can do the same with some ARM boards - maybe
the RockPro which has PCIe?? but not with the majority.

Anyway, let's leave folks to build what works for them: the one thing
I've learned from much of this list is that we're all unique in our
requirements, even if we have much in common.

All the very best, as ever,

Andy 

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Andy Smith]

Hello,

On Sat, Nov 11, 2023 at 04:01:47PM -0800, David Christensen wrote:
> SSD RAID10 is very impressive when everything else matches.  Backups over a
> Gigabit LAN onto SATA III SSD RAID10 does not make sense because Gigabit
> Ethernet is rated for 1 Gbps read/ write and a SATA III SSD RAID10 is rated
> for 24 Gbps read and 12 Gbps write.  I would put HDD's in the backup server
> and put the SSD's in the workstation.

I agree with you when it comes to systems that are used purely for
backups in a style that mimics tape backup, i.e. rare need for
random access, which from what I understand does cover Gene's
situation as Gene is used to using Amanda for backups, which is a
(virtual) tape paradigm.

However, especially in a home setting, people often ask more of "the
server", turning it into something that isn't entirely, or even
primarily, a backup server. If those uses involve random access, SSD
of some kind will be very beneficial.

Also there are quite a few backup technologies that do use random
access a lot. A venerable one often mentioned on this list is
rsnapshot or its basic implementation using rsync. This walks the
entire backup tree at every iteration checking metadata and creating
hardlinks. The period of time spent deciding what to back up and how
often massively exceeds the time spent transferring and writing the
data with these systems. They will also massively benefit from low
latency storage on SSD.

So just as a word of caution -- and I know you know this, David -- I
want to say check how much random access is going on, before
deciding rotational media will cut it.

Thanks,
Andy

PS I stated this before and I have to say it again though: while
   building a dedicated backup system seems like a great idea for
   Gene's use case, the practical situation for Gene is that he's
   been trying for literal years now to make a very simple RAID10
   mdadm work on perfectly serviceable hardware. This should be a
   simple task, but it's not gone well for him and this list is
   unable to get to the bottom of why (I include myself in that, but
   I think it reflects more on communications difficulties than a
   shortcoming of Linux mdadm). I am at a loss as to why, given
   those facts, people are still advising Gene to build an entire
   new system out of parts. It makes sense for the use case but not
   for the user. I don't think it's supportable. For this user I
   would have to still stand by my advice of buying an off-the-shelf
   NAS.

-- 
https://bitfolk.com/ -- No-nonsense VPS hosting

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Stefan Monnier]

> I have always liked ATX tower cases with lots of drive bays, both internal
> and external.  Over time, more products have become available with good
> cooling and low noise.  I have not found a major computer manufacturer who
> makes servers with all of those features, so I build my own:
>
> * Fractal Design Define R5 case
> * 3 @ Fractal Design low-speed 140 mm fans
> * Fractal Design Ion+ 2 Platinum 660 W power supply
> * Intel S1200V3RP motherboard
> * Intel Xeon E3-1200 v3 series processors
> * Dual channel ECC memory
> * LSI 9207-8i HBA with "IT mode" non-RAID firmware
> * Seagate Barracuda and Constellation ES.2 HDD's
> * Intel 520 Series SSD's
> * StarTech 2.5" and 3.5" mobile racks
> * Cable Matters black SATA 6 Gbps cables with locking connectors

My home NAS is in a completely different category:
an ARM SBC with on-board SATA.  Much smaller, extremely quiet (no fan),
and between 5W and 10W of power consumption depending on whether it's
mostly idle (the overwhelmingly common case) or not.


Stefan

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[David Christensen]

On 11/11/23 08:52, Andrew M.A. Cater wrote:

On Fri, Nov 10, 2023 at 10:22:07PM -0500, gene heskett wrote:

On 11/10/23 19:46, David Christensen wrote:

On 11/8/23 02:20, gene heskett wrote:

And I just looked at tht pair, and acc gparted they have both been
pvcreated, so I'll leave then alone and steal the dvd cable, puttin
a new 2T drive if I can rig power to it.


As I previously suggested, and as you previously seemed agreeable to, I
think you should stop working on the Asus and build a backup server.


I'm thinking of making a slow one out of a headless bananapi-5 with a 2T on
every usb3 port as a raid, type to be determined, I rather like the idea of
parity being striped across all 4 disks. I have the drives but not sure of
the usb-sata adapters, need to goto the garage and retrieve that box. That,
and there's only one of me ;o)>  And me is 89 yo with a worn out body. A
pacemaker and some new parts in my heart too.


Are these 2TB SSDs or hard disks? I would counsel very strongly indeed
against using any ARM-based single board computer as a RAID device on
USB connections - they're just *not* up to it.



On 11/11/23 09:05, Stefan Monnier wrote:
> I don't think the issue is whether they're ARM based.
>
> The issue is simply how you connect the disks: in my experience, disks
> connected via USB are simply not quite up to a 24/7 situation,
> especially if the disk is USB-powered.


On 11/11/23 09:37, Pocket wrote:
> I have used ssd drives connected to a RPI4 ever since the 4 came out,
> zero issues.
>
> The RPI4's boot from the ssd drives.
>
> I have 4 SSD drives connected to a single RPI4 currently, using a
> powered USB hub.
>
> One of those drives contains the boot and root filesystems.
>
> BTW that particular RPI4 runs 24/7 as it is my name server, email
> server, web server and backup server for my network.
>
> It has an uptime of 18 months.


On 11/11/23 10:47, Stefan Monnier wrote:
> Hmm...  so maybe the USB connection is not directly relevant either
> and the real issue is the power?


An obvious difference between internal and external drives is physical 
protection.  Internal drives and cables are protected.  Everything gets 
power from the same source (PSU, PCU fed by dual PSU, etc.).  External 
drives, cables, and power adapters can be moved, yanked, disconnected, 
dropped, kicked, subjected to electrostatic discharge, etc..  There are 
more parts to fail and more opportunities for failure with external 
drives than with internal drives.



It is not uncommon for communications establishment to fail with 
external drives.  Similarly, communications re-establishment when the 
computer and/or drive resume from a power saving mode.  Writing and 
testing this kind of software is difficult and you need people with both 
both CS and EE skills.  There is an astronomical number of combinations 
to design and test for.  The code runs rarely.  For reliable 24x365 
operations, the challenge is eliminating everything that can cause 
communications establishment/ re-establishment -- operator steps, 
computer configuration, drive configuration, power failures, cooling 
failures, etc..  If you can find and eliminate all of them, a USB 
external drive can stay connected a very long time.




Get a cheap barebones system that you add memory to in a small-ish size
case with SATA cables to motherboard ports that's Intel/AMD based that
you can then put disks into to format. If you can't get a barebones,
at least get a second hand machine in a tower case.



I have always liked ATX tower cases with lots of drive bays, both 
internal and external.  Over time, more products have become available 
with good cooling and low noise.  I have not found a major computer 
manufacturer who makes servers with all of those features, so I build my 
own:


* Fractal Design Define R5 case
* 3 @ Fractal Design low-speed 140 mm fans
* Fractal Design Ion+ 2 Platinum 660 W power supply
* Intel S1200V3RP motherboard
* Intel Xeon E3-1200 v3 series processors
* Dual channel ECC memory
* LSI 9207-8i HBA with "IT mode" non-RAID firmware
* Seagate Barracuda and Constellation ES.2 HDD's
* Intel 520 Series SSD's
* StarTech 2.5" and 3.5" mobile racks
* Cable Matters black SATA 6 Gbps cables with locking connectors


They are not cheap, small, or light, but they perform well, are easy to 
work on, are reasonably quiet, and everything stays cool.  They have 
plenty of capacity for future upgrades.




Build a simple Debian system on one disk there to format other disks :)



I put my Debian and FreeBSD instances on a single 2.5" SATA SSD.  I keep 
them small -- 1 GB boot, 1 GB swap, and 12 GB root.  I keep my system 
configuration files and working files in a version control system (CVS).




Once you've built a simple Debian system there, you can add mdadm RAID
and use it as a backup storage device to copy off your /home and so on.



For my file server and backup server, primary storage is a ZFS stripe of 
HDD mirrors (e.g. RAID10) with 

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Dan Ritter]

Jeffrey Walton wrote: 
> >From what I've read when comparing OpenMediaVault vs TrueNAS, it
> usually comes down to the power consumption of the mini computer/mini
> pc. 5W can save you $100 USD per year. Probably more now due to
> inflation.


5W * 24h/D * 30 D/M * 12M/Y = 43200 Wh, or 43.2KWh per year

If a KWh costs you: then 43.2KWh is:
Massachusetts:  32c $13.82
California: 30c $12.96
Florida:15c $ 6.48
Germany:42c $18.14
Denmark:37c $15.98
United Kingdom: 33c $14.26

So you need between 25 and 75W of 24/7 power usage to get to
$100 US of savings in a year.

A spinning disk draws about 7W. An SSD draws about 0.05W when
asleep, 1.5W in "active idle", and up to 8W during writes.

-dsr-

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Jeffrey Walton]

On Sat, Nov 11, 2023 at 6:20 PM Dan Ritter  wrote:
>
> Jeffrey Walton wrote:
> > >From what I've read when comparing OpenMediaVault vs TrueNAS, it
> > usually comes down to the power consumption of the mini computer/mini
> > pc. 5W can save you $100 USD per year. Probably more now due to
> > inflation.
>
>
> 5W * 24h/D * 30 D/M * 12M/Y = 43200 Wh, or 43.2KWh per year
>
> If a KWh costs you: then 43.2KWh is:
> Massachusetts:  32c $13.82
> California: 30c $12.96
> Florida:15c $ 6.48
> Germany:42c $18.14
> Denmark:37c $15.98
> United Kingdom: 33c $14.26
>
> So you need between 25 and 75W of 24/7 power usage to get to
> $100 US of savings in a year.

Right. Some can get into the 60W range, so you have to be careful
about what is being selected.

> A spinning disk draws about 7W. An SSD draws about 0.05W when
> asleep, 1.5W in "active idle", and up to 8W during writes.

Jeff

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[gene heskett]

On 11/11/23 15:41, Pocket wrote:


On 11/11/23 13:47, Stefan Monnier wrote:

I have used ssd drives connected to a RPI4 ever since the 4 came out,
zero issues.
The RPI4's boot from the ssd drives.
I have 4 SSD drives connected to a single RPI4 currently, using a 
powered

USB hub.

Hmm...  so maybe the USB connection is not directly relevant either and
the real issue is the power?


I'm forced to agree.  The wall wart supplied with the pi kits is rather 
under powered. I don't run them on less than a 5 volt 5 amp supply, and 
like pocket, they only get rebooted when needsreboot says so after an 
update. In 7 or so years of running a Sheldon lathe built in the 1940's, 
first with an rpi3b which was pushed a bit and an rpi4b that doesn't 
even breath hard, for at last 4, maybe 5 years, I've had one unscheduled 
reboot. That I think is about 100x better uptime than I'm averaging 
running the same linuxcnc software on wintel stuff.  That 5 volt, 5 amp 
supply is powering 5 other interfacing boards to get the job done. One 
of its jobs is running a clone of the linuxcnc.org buildbot.

It Just Works...


 Stefan


That would be my best guess also



Cheers, Gene Heskett.
--
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Jeffrey Walton]

On Sat, Nov 11, 2023 at 1:48 PM Stefan Monnier  wrote:
>
> > I have used ssd drives connected to a RPI4 ever since the 4 came out,
> > zero issues.
> > The RPI4's boot from the ssd drives.
> > I have 4 SSD drives connected to a single RPI4 currently, using a powered
> > USB hub.
>
> Hmm...  so maybe the USB connection is not directly relevant either and
> the real issue is the power?

>From what I've read when comparing OpenMediaVault vs TrueNAS, it
usually comes down to the power consumption of the mini computer/mini
pc. 5W can save you $100 USD per year. Probably more now due to
inflation. But the use cases they discuss often includes transcoding
of video streams, which I don't think is needed in the case of
backups. See, for example,
.

Related, I am getting ready to standup a NAS for my home network.
(Currently I'm doing some half-ass file sharing). The enclosure
hardware on the short list are 
and . The mini computer the
enclosure will be attached to will be USB 3.1 or 3.2 capable for 10
GB/s or 20 GB/s throughput.

Eventually my network will need to be upgraded to at least 2.5 GB/s to
take advantage of the throughput. I'm waiting for prices to drop a
bit. 2.5 GB/s and 5.0 GB/s network cards, switches and Cat 8 cables
are still a bit expensive.

Jeff

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Pocket]

On 11/11/23 13:47, Stefan Monnier wrote:

I have used ssd drives connected to a RPI4 ever since the 4 came out,
zero issues.
The RPI4's boot from the ssd drives.
I have 4 SSD drives connected to a single RPI4 currently, using a powered
USB hub.

Hmm...  so maybe the USB connection is not directly relevant either and
the real issue is the power?


 Stefan


That would be my best guess also

--
It's not easy to be me

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Stefan Monnier]

> I have used ssd drives connected to a RPI4 ever since the 4 came out,
> zero issues.
> The RPI4's boot from the ssd drives.
> I have 4 SSD drives connected to a single RPI4 currently, using a powered
> USB hub.

Hmm...  so maybe the USB connection is not directly relevant either and
the real issue is the power?


Stefan

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Pocket]

On 11/11/23 12:05, Stefan Monnier wrote:

Are these 2TB SSDs or hard disks? I would counsel very strongly indeed
against using any ARM-based single board computer as a RAID device on
USB connections - they're just *not* up to it.

I don't think the issue is whether they're ARM based.

The issue is simply how you connect the disks: in my experience, disks
connected via USB are simply not quite up to a 24/7 situation,
especially if the disk is USB-powered.


 Stefan



I have used ssd drives connected to a RPI4 ever since the 4 came out, 
zero issues.


The RPI4's boot from the ssd drives.

I have 4 SSD drives connected to a single RPI4 currently, using a 
powered USB hub.


One of those drives contains the boot and root filesystems.

BTW that particular RPI4 runs 24/7 as it is my name server, email 
server, web server and backup server for my network.


It has an uptime of 18 months.


--
It's not easy to be me

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[fxkl47BF]

just my two sense
not advice or promotion
i've used this device for about 2.5 years with 6tb harddrives in raid 1
i have partitions on the raid for the os, debian, and the rest for backups
no problems so far


https://ameridroid.com/products/odroid-hc4

Re: Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Stefan Monnier]

> Are these 2TB SSDs or hard disks? I would counsel very strongly indeed 
> against using any ARM-based single board computer as a RAID device on
> USB connections - they're just *not* up to it.

I don't think the issue is whether they're ARM based.

The issue is simply how you connect the disks: in my experience, disks
connected via USB are simply not quite up to a 24/7 situation,
especially if the disk is USB-powered.


Stefan

Hardware for a back up server? [WAS Re: How to use dmsetuup?]

[Andrew M.A. Cater]

On Fri, Nov 10, 2023 at 10:22:07PM -0500, gene heskett wrote:
> On 11/10/23 19:46, David Christensen wrote:
> > On 11/8/23 02:20, gene heskett wrote:
> > > And I just looked at tht pair, and acc gparted they have both been
> > > pvcreated, so I'll leave then alone and steal the dvd cable, puttin
> > > a new 2T drive if I can rig power to it.
> > 
> > 
> > As I previously suggested, and as you previously seemed agreeable to, I
> > think you should stop working on the Asus and build a backup server.
> > 
> I'm thinking of making a slow one out of a headless bananapi-5 with a 2T on
> every usb3 port as a raid, type to be determined, I rather like the idea of
> parity being striped across all 4 disks. I have the drives but not sure of
> the usb-sata adapters, need to goto the garage and retrieve that box. That,
> and there's only one of me ;o)>  And me is 89 yo with a worn out body. A
> pacemaker and some new parts in my heart too.
> 

Gene,

Are these 2TB SSDs or hard disks? I would counsel very strongly indeed 
against using any ARM-based single board computer as a RAID device on
USB connections - they're just *not* up to it.

Get a cheap barebones system that you add memory to in a small-ish size 
case with SATA cables to motherboard ports that's Intel/AMD based that
you can then put disks into to format. If you can't get a barebones,
at least get a second hand machine in a tower case.

Build a simple Debian system on one disk there to format other disks :)
Once you've built a simple Debian system there, you can add mdadm RAID
and use it as a backup storage device to copy off your /home and so on. 

> Startech adapters are working very well to a pair of smaller SSD's on the
> rpi4b that runs my old (80+) Sheldon 11"x54" lathe, teaching it new tricks
> it never dreamed of doing 80+ years ago. Metric or imperial, it doesn't
> care.  Even cuts threads I've invented.  I have a complete linuxcnc buildbot
> on that pi. The latest bpi runs at 2 gigahertz which is about twice as fast
> as the pi's.

USB adapters will work well until you are _absolutely_ reliant on them,
then there will be a problem in my experience :(
> 
> > > This mobo also claims to be able to do the intel version of a raid
> > > on its own sata ports.  Does anyone here have experience doing that?
> > 
> > 
> > Yes, but I prefer software RAID -- because I can move the disks to
> > another computer with different hardware and the arrays will still work.
> >  Hardware RAID typically requires compatible hardware.
> > 

Yes, absolutely agreed with David on this.

> > 
> > David
> > 
> > .
> Understood before hand.  Thanks David, take care & stay well.
> 

All the very best, as ever,

Andy
[amaca...@debian.org]
> Cheers, Gene Heskett.
> -- 
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author, 1940)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
>