Installing a DroboS with Ubuntu 10.10 and a 16TB LUN size and ext4
Christoper Blunck
I've been a proud owner of drobos for years. I think it's a fantastic
product. I've been through the price and pain of RAID and Drobo's
BeyondRAID is simply put ... wonderful.
That being said I also really enjoy using Linux as my back office
fileserver. I don't know what my desktop/laptop environment will be
every 6 months and I need a backing store I can send videos, photos,
and other files to. Enter Drobo.
I wanted to document my installation process for a Drobo S under
Ubuntu 10.10. I hope this will help some other folks save some
time...
I purchased 2 x 3TB Western Digital (WD) SATA drives from NewEgg for $150 each.
When the DroboS arrived I attached it to my Ubuntu 10.10 server. I
ran "tail -f /var/log/messages" so I could watch the logs and see what
device was reported when the DroboS attached. For me that was
/dev/sdi. I then used drobo-utils 0.6.2.2 and ran "drobom list".
That command reported my other 2 drobo units (first gen Drobo units)
but it failed to report my DroboS. Google searching and help file
inspection inspired me to run "drobom list" with -v 16 so I could see
the descriptions. My DroboS reported itself as a "USB 3.0 " (note the
extra space at the end). I also noted that drobom detected other USB
attached storage devices and said they were drobo units. Not sure why
they said that but in the end the list of drobo units only included my
first gen drobo units and not my DroboS. I then tried to use the "-s
'USB 3.0 '" argument to drobom with the list command but it did not
report my drobo.
I then inserted my first 3TB drive. The DroboS red light kept
blinking. I figured it was related to the fact that I was trying to
initialize under Linux. I was wrong. I did some google searching and
it turns out that you need version 2.1.1 of the DroboS firmware in
order to support drives > 2TB. I disconnected my DroboS from my Linux
box. I then installed the Drobo Dashboard for OSX. I then connected
my DroboS and discovered my DroboS had version 2.0.4 firmware. I
updated the firmware of the Drobo as well as the dashboard software.
I let the various OS and Drobo reboots run.
I then connected my 2.1.1 firmware DroboS to my Ubuntu 10.10 box and
let it boot up. I saw /dev/sdi showed up from /var/log/message
tail'ing. I then tried "drobom -d /dev/sdi list" but it still failed
to detect.
I then inserted my first 3TB drive. After inserting and about 30
seconds the top red light turned green. The 2.1.1 firmware worked and
my DroboS detected the 3TB drive!
I then retried "drobom list" but no luck.
I remembered that several years ago when I set up my first gen drobo I
had to mess around with "trusted LUN sizes". Basically the concept
there was you would say "this LUN is 8TB - treat it as such..." Then
when you ran the various mkfs commands they would say "ok ... I'll
format an 8TB filesystem ... ho hum" (even though you really only have
1TB of space available).
I remember too that back then I had to use Windows to do the actual
LUN size setting. But ... that was several years ago so I was hoping
things might've gotten better and I tried to do it pure Linux with
drobom. No luck...
I attached my DroboS to my iMac. I added the second drive so I had 2
x 3TB drives in my DroboS. I ran the Drobo Dashboard and asked the
dashboard to format the drobo as HFS. It prompted for confirmation, I
agreed, and then chose 16TB as the max size. I let the Dashboard
format for a few minutes. I then disconnected from my iMac and
reattached to Linux.
When I reattached to Linux I ran parted and used the "print" command.
There was only 1 partition displayed in parted: /dev/sdi1. It was
tiny - a few hundred MB.
On a whim I decided to throw a "mkfs.ext4 /dev/sdi2" at the drobo.
Low and behold I'm looking at a 16TB ext4 formatted filesystem.
Anyhow... I wanted to type this up in case anyone else has recently
purchased a DroboS and wants to run a single 16TB filesystem off it
under Ubuntu.
Key points:
1.) Use OSX/Windows Drobo Dashboard to upgrade firmware to 2.1.1 or higher
2.) Use OSX/Windows Drobo Dashboard to "format" the drobo initially
and choose 16TB as the size.
3.) Connect the DroboS to Ubuntu, tail -f /var/log/messages to
verify connectivity, and parted /dev/<whatever> followed by "print" to
make sure you have a partition
4.) mkfs.ext4 /dev/<dev>2 (note: partition 2!!!) to format the filesystem
-c
--
Christopher Blunck
ch...@thebluncks.com
--
Christopher Blunck
ch...@thebluncks.com
Jens Langner
first of all, thanks for the nice report on Ubuntu 10.10 and 16TB LUN. I
also have a DroboS with eSATA connected to an Ubuntu 10.10 machine and
have it running without any issues so for (> 1 year) with a 8TB LUN.
Christoper Blunck schrieb:
[...]
> Key points:
> 1.) Use OSX/Windows Drobo Dashboard to upgrade firmware to 2.1.1 or higher
> 2.) Use OSX/Windows Drobo Dashboard to "format" the drobo initially
> and choose 16TB as the size.
> 3.) Connect the DroboS to Ubuntu, tail -f /var/log/messages to
> verify connectivity, and parted /dev/<whatever> followed by "print" to
> make sure you have a partition
> 4.) mkfs.ext4 /dev/<dev>2 (note: partition 2!!!) to format the filesystem
Just a short side node on (4). Are you really sure that ext4 is working
fine (also over time)? Because AFAIK only ext2/ext3 is supported and
using ext4 may run into problems for the thin provising capabilities so
that it may happen that you drobo starts filling up without identifying
that you also deleted stuff.
Please also note that I also formatted my drobo on OSX first and set the
LUN size there to 8TB as well. However, after reattaching it to my
Ubuntu box I simply reinstalled the partition with parted and have my
data now on /dev/sde1 and not 2. And I have it now running > 1 year
without any issues so far.
best regards,
jens
--
Jens Langner, Dresden/Germany
http://www.jens-langner.de/
Jens Langner
yet with my DroboS. However, my eSATA connection gives me a net speed of
about 50-60MB/s when accessing it which IMHO is pretty fast. And I dunno
(and partly doubt) that it would get any faster with USB3.0. Please
note, however, that I do not have the latest firmware installed in my
DroboS. But as said, it works flawlessly since over a year now with
Linux, an 8TB LUN and ext3.
best regards,
jens
Christopher Blunck schrieb:
> Hi Jens,
>
> Funny you should ask about the ext4. I woke up this morning and
> discovered that my DroboS was unresponsive under Linux.
>
> While formatting last night I inadvertently mkfs.ext4'ed both /dev/
> sdi1 and /dev/sdi2 (on my other drobo units the first partition was
> where I formatted so I instinctively went for that partition on my
> DroboS). The format of /dev/sdi1 was nearly instantaneous because I
> believe that partition was really small (a few hundred MB?). The /dev/
> sdi2 partition was the 16TB partition who's format took forever...
>
> Tonight I'm planning on re-initializing my DroboS under OSX and then
> re-formatting. I'll probably go with ext3 to be safe... I'll send
> out another email with follow up notes.
>
> How has your eSATA experience been? I was thinking about going that
> route but hesitated because I'm attaching my Drobo to a 2U rackmount
> server that's pretty old. I think I'd have a difficult time locating
> an eSATA card that would fit in the form factor I need. I would
> actually prefer to go with USB 3.0 because I read that it supports 3Gb/
> s transfer rates!
>
>
> -c
Peter.A.Silva
using ext4 on any Drobo. The best case is that it will just fill up
prematurely and start running really slowly until you offload it.
Whenever you want to try a new configuration, you need to test it by
filling it up (watching the lights light up as stuff is added.) then
empty it out. It may take an hour or two, but the capacity lights
should drop down to reflect current use. If they don't, you will have
problems. The only way I have seen to correct that is to rebuild the
file system from scratch. There are many stories on this forum of
people losing data this way (LUN sizes, drobo models, and file systems
vary, results don't.) People claim things, and then a few months
they come back, and things are never rosy. Make sure you test this
thoroughly before you commit to it (ie. you need to be able to offload
it.)
I believe the only configuration that will work on your hardware is 8
TiB ext3. If you want 16, You need to create two 8 TiB ext3's, and
mash them up with mhddfs or some other unions fs. If you don't
believe me, that's fine, just run the above tests with your
configuration, and let me know how they turn out. Data wins.