NASLite Network Attached Storage

Hi all !

I've some newbie questions, hope someone can help since I couldn't find answers around...

1)I've created the array (RAID1 based on 2 disks) and installed naslite without any problem at all. Now how do I get sure RAID is working properly ? I mean, how do I get sure that BOTH the hard drives are used so the array is up and running ? Here are some lines from my syslog, I think the answer is here...

# Jan 11 22:20:02 user.warn kernel: GDT-HA: Storage RAID Controller Driver. Version: 3.04
# Jan 11 22:20:02 user.warn kernel: GDT-HA: Found 0 PCI Storage RAID Controllers
# Jan 11 22:20:02 user.warn kernel: 3ware Storage Controller device driver for Linux v1.02.00.037.
# Jan 11 22:20:02 user.notice kernel: scsi1 : Found a 3ware Storage Controller at 0xc800, IRQ: 5, P-chip: 1.3
# Jan 11 22:20:02 user.info kernel: scsi1 : 3ware Storage Controller
# Jan 11 22:20:02 user.warn kernel: Vendor: 3ware Model: Logical Disk 0 Rev: 1.0
# Jan 11 22:20:02 user.warn kernel: Type: Direct-Access ANSI SCSI revision: 00
# Jan 11 22:20:02 user.debug kernel: libata version 1.20 loaded.
# Jan 11 22:20:02 user.warn kernel: Attached scsi disk sda at scsi1, channel 0, id 0, lun 0
# Jan 11 22:20:02 user.warn kernel: SCSI device sda: 312579760 512-byte hdwr sectors (160041 MB)
# Jan 11 22:20:02 user.info kernel: /dev/scsi/host1/bus0/target0/lun0: p1
# Jan 11 22:20:02 user.info kernel: raw1394: /dev/raw1394 device initialized
# Jan 11 22:20:02 user.info kernel: sbp2: $Rev: 1074 $ Ben Collins


2)So, assuming the array is working properly, what's going to happen if one hd will fail for some reasons such: damanged clusters, electronic board failure etc. Do NASlite will recognized the degradated array and warn me using pcspeaker beeps ? I've red in manual that SMART is not available in array, so i was wondering how do I discover a drive failure... I'm a little confused


3)What's the meaning of this line appeared in my syslog file ?
# Jan 11 22:20:02 user.err kernel: ieee1394: sbp2: Driver forced to serialize I/O (serialize_io = 1)
I've turned off from mobo bios the ieee1394 controller so I think it's a normal message, isn't it ?


Thank you in advace for your kind help, and congratulation to Tony and to the Naslite team for this little excellent software ! Let's keep this way guys !!!

Hi and welcome to our still growing family of naslite users

It looks like your 3ware card is recognised, so you can read and write from
and to the nas
The mirror work is done by the hardware raid card
so in an event of diskfailure, the raidcard will warn you.
you should find more info in the card's manual
There are a couple of guys here who use 3ware raidcards, I'm sure they can
tell you more.

Perhaps something to think about:
Do you have a backup raidcard, in the event the card itself fails?
(a.k.a. how paranoid are you)
I do, you know. And I have my data synced on a different drive in the nas

Do you know who they are ?

No, if the raidcard will fail I will extract one disk, put on my pc and copy the data... I know that it is not a good solution, but raidcards are very expensive and I couldn't afford a spare one.
Well, could I ask Naslite to mirror the array into an external 2.5" HD with the same capacity ? I can do it using mirror functionality right ?

Correct
Or you can install a normal 3.5" drive and mirror to that one
I do somthing similar, but the other way around
My primary drive is a 750GB IDE drive
and this one is synced to the raid 5 array
and the raid5 array "protects itself" being raid 5, you could use raid 1 there to but 5 gives more storage with the same amount of disks


you're almost set for life with a solid backup strategy

The software daily mirror is a very powerful function within NASLite - I used it before I got my first Hardware RAID card for all my "critical" data (kids photos, etc.)
I totally agree with this last point : RAID6 "better" than RAID1 "better" than RAID5 ("better" = less likelihood of losing data when rebuilding after single drive failure). To use RAID5, you would need at least 3 drives (you create an array with a usable size of (n-1) x size of smallest drive, nth drive = parity, in this case n=3).

I've had no problems (not of my own making) with my 3Ware cards - both extremely solid (if you don't foul up the IRQ assignment....). Also, when I have had a problem, it has been reported in the SYSLOG in NASLite.

p.s. Tony, Ralph - *Love* the new forums - I now stay logged in between sessions!!!!

Ok, thanks for your advice However I still haven't understood if it is possibile or not to see in syslog file, how many phisical hard drives are used...
Another question, maybe NickC you could help me: what is cache write functionality in 3ware ctrl and what is used for ?
Thanks again for your kind help

Emmanuele

In the syslog, you should find something like:


Which tells you that there are 3 "SCSI" disks at scsi1, channel 0, id 0, lun0; scsi1, channel 0, id 2, lun 0 and scsi2, channel 0, id 4, lun 0. These are all RAID arrays - 1 x 250GB R1 and 2 x 1.5TB R5.

The write cache functionality allows the array to run faster, however, if there is a power failure during a write operation, more data could be lost as it may still reside in the HDD's cache (typically 2MB to 16MB) rather than on the HDD platter.

Thanks for your clear explanation on write cache NickC !
What I see in the the syslog file is only the following:

# Jan 11 22:20:02 user.warn kernel: GDT-HA: Storage RAID Controller Driver. Version: 3.04
# Jan 11 22:20:02 user.warn kernel: GDT-HA: Found 0 PCI Storage RAID Controllers
# Jan 11 22:20:02 user.warn kernel: 3ware Storage Controller device driver for Linux v1.02.00.037.
# Jan 11 22:20:02 user.notice kernel: scsi1 : Found a 3ware Storage Controller at 0xc800, IRQ: 5, P-chip: 1.3
# Jan 11 22:20:02 user.info kernel: scsi1 : 3ware Storage Controller
# Jan 11 22:20:02 user.warn kernel: Vendor: 3ware Model: Logical Disk 0 Rev: 1.0
# Jan 11 22:20:02 user.warn kernel: Type: Direct-Access ANSI SCSI revision: 00
# Jan 11 22:20:02 user.debug kernel: libata version 1.20 loaded.
# Jan 11 22:20:02 user.warn kernel: Attached scsi disk sda at scsi1, channel 0, id 0, lun 0
# Jan 11 22:20:02 user.warn kernel: SCSI device sda: 312579760 512-byte hdwr sectors (160041 MB)
# Jan 11 22:20:02 user.info kernel: /dev/scsi/host1/bus0/target0/lun0: p1
# Jan 11 22:20:02 user.info kernel: raw1394: /dev/raw1394 device initialized
# Jan 11 22:20:02 user.info kernel: sbp2: $Rev: 1074 $ Ben Collins

So it should see only one disk ? I tried to degradate the array by removing the first HD and the the other one, of course not simultaneously. In both case the array warm me saying the cluster is degradated, but NO SOUND are eared fron the pc. Not even int the case I ask my controller to force the cluster rebuild... I'm still not convicend everithing is working in the right way...

Your card seems to be seeing 1 x 160GB drive. I've had the RAID beeps from NASLite - very annoying until I worked out what the (user installation / motherboard BIOS configuration) problem was. I think at that time my RAID was being degraded after about every second boot (I power-down overnight as my NAS is a home media server).

NickC, I tried unplugging both drives, not simultaneously, and I see that they contain the same data... So the mirror is working properly...
I still don't understand why the kernel only see one drive... Perhaps, that should be normal ? I think that this issue is related in the ctrl bios... However, the mirror is working flawlessy, so I don't care it very much
Thanks for your patience and your kind explanation NickC
Bye !

The capacity of a RAID1 drive = 1 x (size of smaller drive in the RAID1 array), i.e. everything that can be written to the smaller drive and also the bigger drive.

If you can only see 1 drive then the RAID1 is working perfectly - that's what it does - uses 2 drives to store your data in 2 (safer) places at once, transparently and instantaneously.

With a 4 port SATA RAID card, you could have a 480GB RAID5 array by adding 2 HDD's of the same size (or bigger but you "lose" the extra space). However, the easiest way to add the drives is to move all of the data off and reconfigure in the 3Ware BIOS. I've done that a couple of times and although time consuming, I feel it is more secure.

I'm glad you're getting to grips with NASLite, I've been using it for just over a year now and I'm still delighted with its simplicity and security.