DIY NAS server with RAID 5

[Lady Margaret Thatcher]

I would like to build up a NAS server with RAID 5. This would be used
with Windows XP today and eventually Linux machines.

Can anyone recommend an OS? Are there products that contain both the
OS and the "applications" for a NAS server?

For RAID 5, is it possible to start with say 4 drives and then add a
5th or 6th drive, the idea being that the system automatically
rebuilds itself to incorporate the new drives? Are there products
that do this?

Thanks

--thatcher--

 

[Arno Wagner]

I would like to build up a NAS server with RAID 5. This would be used
with Windows XP today and eventually Linux machines.

Can anyone recommend an OS? Are there products that contain both the
OS and the "applications" for a NAS server?

The classical choice for low-cost is Linux with SAMBA/NFS
as filesystem export and software RAID.

For RAID 5, is it possible to start with say 4 drives and then add a
5th or 6th drive, the idea being that the system automatically
rebuilds itself to incorporate the new drives? Are there products
that do this?

Linux experiments with that in the newest Kernel versions.
I have no idea how stable or usable this is at the moment.
However you also need to extend the filesyste or create new
partitions. This may or may not require one or several reboots
to do and may also require a separate disk for the OS or a
maintenance system to be on.

Arno

 

[Lady Margaret Thatcher]

Previously Lady Margaret Thatcher <Was_at_10_Downing_Street@bad_for_the_uk.org> wrote:

The classical choice for low-cost is Linux with SAMBA/NFS
as filesystem export and software RAID.

For my application, which is _reliable_ bulk storage of large numbers
of files, this may be good enough. Any file needing local editing
will be edited on a local system, with local scratch space.

Any hardware RAID controllers that can do this?

Linux experiments with that in the newest Kernel versions.

Is this a kernel feature, or an extension by one of the distros?

I have no idea how stable or usable this is at the moment.
However you also need to extend the filesyste or create new
partitions. This may or may not require one or several reboots
to do and may also require a separate disk for the OS or a
maintenance system to be on.

Reboots aren't the big issue. Separate disk may be an issue, but if
it is simply a separate partition for the OS, then I might do that
with the OS drive bigger than all the other drives.

 

[Arno Wagner]

For my application, which is _reliable_ bulk storage of large numbers
of files, this may be good enough. Any file needing local editing
will be edited on a local system, with local scratch space.

Any hardware RAID controllers that can do this?

Not that I know of.

Is this a kernel feature, or an extension by one of the distros?

In 2.6.17 it is a kernel feature. This is a bit beyond of what
distros can do. Note that 2.6.17 is not out yet. May take
aonter week or two.

Reboots aren't the big issue. Separate disk may be an issue, but if
it is simply a separate partition for the OS, then I might do that
with the OS drive bigger than all the other drives.

If you do the RAID on parition layer in logical parttitions
or in primary partitions at the end of the disk and
put the OS in a primary partition at the start of
the disk, I would expect that you can extend the partition
size of the RAID, while an OS is running from another
partition on the same drive. If not, you can also boot
from CD or floppy to do the partition enlargement (likely
with GNU parted) and then extend the RAID with the native
system running from the HDD. Its may also be possible
to extend the partition, reboot and then extend the RAID.
I really cannot tell at the moment.

Arno

 

[Arno Wagner]

For my application, which is _reliable_ bulk storage of large numbers
of files, this may be good enough. Any file needing local editing
will be edited on a local system, with local scratch space.

Any hardware RAID controllers that can do this?

Is this a kernel feature, or an extension by one of the distros?

Reboots aren't the big issue. Separate disk may be an issue, but if
it is simply a separate partition for the OS, then I might do that
with the OS drive bigger than all the other drives.

Correction: I am confused. Of course you would extend the RAID _first_
by adding another disk and changing the RAID size and _then_ extend
the filesystem on it. That should not be a problem while the system is
running, as long as you do not need the filesystem(s) on the RAID
mounted. I.e. it should works if you have the OS in a separate
partition. Expect maybe 5GB for a full Linux installation.

Arno

 

[dubba]

FreeNAS

I have not tried this but can be a good starting point - http://www.freenas.org/

Dubba