Magnus Warker writes:
>Hallo Leute,

I'll answer in English, which is the preferred language in this group.

>ich bin auf der Suche nach geeigneter Hardware für einen File-Server. Er
>soll mit Debian laufen und ein Hardware-RAID mit SATA-Platten haben.

What for? Our file server all run with software RAID 1 using the md
driver, an that works fine. It also means that we don't need to have
the same hardware RAID chip available when the hardware fails (for
RAID1 this is supposedly not a problem, but better safe than sorry).

>Darüber hinaus sollte er einen Gigabit-Ethernet-Anschluss haben und
>ansonsten möglichst wenig Geräusche und Hitze produzieren. Es soll kein X
>oder sonst was drauf laufen, so dass eine Grafikkarte nur für Textmodus
>gebraucht wird. Sound ist ebenfalls nicht erwünscht.

You probably want ECC memory, so I would look for a single-CPU-socket
server board (these typically have simple on-board graphics); you can
find such things from Tyan, Supermicro and Intel, for example. Any of
these will have at least one (usually two) Gb Ethernet ports. For
coolness, get a slow Athlon 64 EE or Core 2 Duo (=Xeon 30xx) CPU, and
if you get an AMD CPU, use the ondemand governor to run is at a cool
and low clock rate most of the time. For quietness, drive the CPU fan
with fancontrol (this takes some setup work, though).

If you don't want ECC, an EPIA board might be sufficient.

- anton
--
M. Anton Ertl Some things have to be seen to be believed
anton@mips.complang.tuwien.ac.at Most things have to be believed to be seen
http://www.complang.tuwien.ac.at/anton/home.html

Dear Anton,

>>ich bin auf der Suche nach geeigneter Hardware für einen File-Server. Er
>>soll mit Debian laufen und ein Hardware-RAID mit SATA-Platten haben.
>
> What for? Our file server all run with software RAID 1 using the md
> driver, an that works fine.

Some time ago I had a file server running RH with two SCSI disks and a
software RAID. The problem there was that the driver that realized the
software RAID was not available before it was read from disk. On the other
hand the disk was not available before the driver was installed. We had to
install a separate boot disk besides the RAID set. Since this time I have a
little preference for hardware RAID solutions. Maybe this opinion is not
adequate. However, does this option have an impact on the choice of
motherboard?

>>Darüber hinaus sollte er einen Gigabit-Ethernet-Anschluss haben und
>>ansonsten möglichst wenig Geräusche und Hitze produzieren. Es soll kein X
>>oder sonst was drauf laufen, so dass eine Grafikkarte nur für Textmodus
>>gebraucht wird. Sound ist ebenfalls nicht erwünscht.

> You probably want ECC memory,

Is this a special type of RAM with few heat or few power consumption?

> so I would look for a single-CPU-socket server board
> (these typically have simple on-board graphics);

Did I understand this correctly? Single-CPU-boards in general come with ECC
memory and simple onboard graphics, in contrast to Multi-CPU-boards?

> Any of these will have at least one (usually two) Gb Ethernet ports. For
> coolness, get a slow Athlon 64 EE or Core 2 Duo (=Xeon 30xx) CPU, and
> if you get an AMD CPU, use the ondemand governor to run is at a cool
> and low clock rate most of the time. For quietness, drive the CPU fan
> with fancontrol (this takes some setup work, though).

I tend to an AMD board, because I made good experience with the cool & quiet
technology. But how can I select those AMD boards that have the properties
you mentioned? Just looking for single-CPU-boards?

Thank you
Magnus

Magnus Warker writes:
>Dear Anton,
>
>>>ich bin auf der Suche nach geeigneter Hardware für einen File-Server. Er
>>>soll mit Debian laufen und ein Hardware-RAID mit SATA-Platten haben.
>>
>> What for? Our file server all run with software RAID 1 using the md
>> driver, an that works fine.
>
>Some time ago I had a file server running RH with two SCSI disks and a
>software RAID. The problem there was that the driver that realized the
>software RAID was not available before it was read from disk. On the other
>hand the disk was not available before the driver was installed.

If this was still a problem, with hardware RAID, you would have the
same problem. Hardware RAID needs a driver, too.

Fortunately, at least with software RAID on Debian (and probably all
other important distributions) this is not a problem: The drivers are
all in an initial RAM disk (initrd), which is loaded by the boot loader
together with the kernel.

The only thing you have too look out for is that your boot file system
(where the kernel and the initrd reside) is on a RAID level supported
by your boot loaded, i.e., RAID1 or no RAID. The boot file system is
small (a few dozen MB), so even if you otherwise use RAID5, you won't
lose much space by using RAID1 there.

If your boot file system is RAID1, I recommend using LILO instead of
GRUB, because LILO supports installing itself on RAID1 out of the box
(with GRUB, you normally have the kernel and initrd on RAID1, but the
boot sector and maybe some other stuff is on only one disk, and if
that disk fails, you need to install GRUB on a different one before
you can boot).

If you really want to go with hardware RAID, buy two RAID controllers
(i.e., two motherboards if the controller is on the motherboard) so
you still can access the disk if one controller dies.

> However, does this option have an impact on the choice of
>motherboard?

Many current motherboards have some hardware RAID functionality
(usually fakeraid, though, which combines the drawbacks of hardware
and software RAID), but Linux support is not always there.

>> You probably want ECC memory,
>
>Is this a special type of RAM with few heat or few power consumption?

No, it's normal RAM with additional bits that are used for error
correction (kind of like RAID 5 for RAM). This reduces the chance
that your data is corrupted by the file server. It's a little more
expensive, though, and you need a server motherboard, which is usually
quite a bit more expensive.

>> so I would look for a single-CPU-socket server board
>> (these typically have simple on-board graphics);
>
>Did I understand this correctly? Single-CPU-boards in general come with ECC
>memory and simple onboard graphics, in contrast to Multi-CPU-boards?

No, server boards typically support ECC memory (you still have to buy
that extra:-) and come with simple on-board graphics, in contrast to
"desktop" boards. The single-CPU-socket spec is there because you
don't need more for a file server with a single Gb Ethernet, and such
servers are cooler, quieter, and cheaper.

>I tend to an AMD board, because I made good experience with the cool & quiet
>technology. But how can I select those AMD boards that have the properties
>you mentioned? Just looking for single-CPU-boards?

Look for Tyan boards, maybe also ASUS (Supermicro and Intel don't do
boards for AMD CPUs). AFAIK most others don't support ECC, even
though this is a feature of the Athlon 64 (X2) and it's probably just
some BIOS support that's missing.

Maybe something like the Tyan Tomcat n3400B (S2925). We have two
machines with the similar, but earlier Tomcat K8E (S2865), and are
happy with them.

For ASUS, it's hard to find out if a board supports ECC.

- anton
--
M. Anton Ertl Some things have to be seen to be believed
anton@mips.complang.tuwien.ac.at Most things have to be believed to be seen
http://www.complang.tuwien.ac.at/anton/home.html