Entries Tagged as 'Storage'

Ubuntu – RAID Creation

I think learning how to use mdadm (/sbin/mdadm) is a good idea, but in Ubuntu Desktop you can use Disk Utility (/usr/bin/palimpsest) to create most any of your RAID (“multiple disk”) configurations.

In Disk Utility, just access “File->Create->Raid Array…” on the menu and choose the options.  Before doing that, you might want to clear off the drives you’re going to use (I generally create a fresh GTP partition to insure the drive is ready to be used as a component of the RAID array).

Once you’ve created the container with Disk Utility; you can even format it with a file system; however, you will still need to manually add the entries to /etc/mdadm/mdadm.conf and /etc/fstab.

One other minor issue I noticed.

I gave my multiple disk containers names (mirror00, mirror01, …) and Disk Utility will show them mounted on device /dev/md/mirror00 — in point of fact, you want to use device names like /dev/md0, /dev/md1, … in the /etc/mdadm/mdadm.conf file.  Also, once again, I highly recommend that you use the UUID for the array configuration (in mdadm.conf) and for the file system (in fstab).

Originally posted 2010-07-12 02:00:33.

Ubuntu – Disk Utility

When you install Ubuntu 10.04 Desktop, the default menu item for Disk Utility isn’t extremely useful; after all, it’s on the System->Administration menu, so you would assume that it’s meant to administer the machine, not just view the disk configuration.

What I’m alluding to is that by default Disk Utility (/usr/bin/palimpsest) is not run with elevated privileges (as super-user), but rather as the current user — which if you’re doing as you should be, that’s means you won’t be able to effect any changes, and Disk Utility will probably end up being a waste of time and effort.

To correct this problem all you need do is modify the menu item which launches Disk Utility to elevate your privileges before launching (using gksu) — that, of course, assumes that you’re permitted to elevate your privileges.

To do add privilege elevation to disk utility:

  1. Right click your mouse on the menu bar along the top (right on system is good) and select ‘edit menu items’
  2. Navigate down to ‘administration’ and select it in the left pane
    Select ‘disk utility’ in the right pane
  3. Select ‘properties’ in the buttons on the right
  4. Under ‘command’ prefix it with ‘gksu’ or substitute ‘gksu /usr/bin/palimpsest’ (putting the entire path there)
  5. Then click ‘close’ and ‘close’ again…

Originally posted 2010-06-27 02:00:33.

Disk Bench

I’ve been playing with Ubuntu here of late, and looking at the characteristics of RAID arrays.

What got me on this is when I formatted an ext4 file system on a four drive RAID5 array created using an LSI 150-4 [hardware RAID] controller I noticed that it took longer than I though it should; and while most readers probably won’t be interested in whether or not to use the LSI 150 controller they have in their spare parts bin to create a RAID array on Linux, the numbers below are interesting just in deciding what type of array to create.

These numbers are obtained from the disk benchmark in Disk Utility; this is only a read test (write performance is going to be quite a bit different, but unfortunately the write test in Disk Utility is destructive, and I’m not willing to lose my file system contents at this moment; but I am looking for other good benchmarking tools).

drives avg access time min read rate max read rate avg read rate

ICH8 Single 1 17.4 ms 14.2 23.4 20.7 MB/s
ICH8 Raid1 (Mirror) 2 16.2 ms 20.8 42.9 33.4 MB/s
ICH8 Raid5 4 18.3 ms 17.9 221.2 119.1 MB/s
SiL3132 Raid5 4 18.4 ms 17.8 223.6 118.8 MB/s
LSI150-4 Raid5 4 25.2 ms 12.5 36.6 23.3 MB/s

All the drives used are similar class drives; Seagate Momentus 120GB 5400.6 (ST9120315AS) for the single drive and RAID1 (mirror) tests, and Seagate Momentus 500GB 5400.6 (ST9500325AS) for all the RAID5 tests.  Additionally all drives show that they are performing well withing acceptable operating parameters.

Originally posted 2010-06-30 02:00:09.

Google Music

Well that didn’t take long.

I’ve used a little of my time this week to get more of my digital music library together… and now I’m over the limit of Google Music (and I can tell you it doesn’t handle it gracefully).

But it was pretty obvious from the start that managing the Google Music storage wasn’t really going to be easy.

And I haven’t even finished uploading all my music — I haven’t even started on symphonic and Broadway tunes; and I’d guess I was about 70% through my rock/alternative/dance/country collection…

Yes, I could probably eliminate some music that I would probably never listen to; but the whole thing with cloud storage is that it’s supposed to be there when you want it no matter where you are… if I were always going to stay at home, I’d have access to all my music without the effort.

It’s a pretty safe bet that I’ll be using Amazon music storage by the end of the year, and just go ahead and pay them another $20 per year… the advantage to that is that they do support downloading your music — so I can view the $20 as simply a reasonable fee to backup my music off site.

Originally posted 2011-10-19 02:00:00.

Seagate Firmware Issues

If you own a Seagate hard drive in the Baracuda 7200.11, or Barracuda ES.2 (SATA only), or Maxtor DiamondMax 22 series you might want to read on…

Seagate has confirmed that a number of issues customers have been seeing in 500GB, 750GB, 1TB, and 1.5TB drives is because of an issue with firmware (it also affects other drives, but apparently is seen most often in the “larger” drives).

There have been a number of write ups on the internet about this problem, and Seagate released firmware SD17 in December 2008 which they believed fixed the problems; and then SD1A in January 2009 which again they believed fixed the problems; but reports indicated that these firmware revisions may actually create one of the very problems Seagate is attempting to address.

The firmware issues can adversely effect the drives performance or it can render the drive totally useless (brick mode).

In an effort to prevent worse PR than Seagate is already suffering for this problem, they have stepped forward to assure everyone that they are working on the issues, that the drives have five year warranties (three for Maxtor), and that they will pay the costs for data recovery service if the drive bricks and cannot be used.

I’ll take this opportunity to remind everyone that Seagate is a California based company; and California has a “lemon law” and fairly strict consumer protection when a vendor advertises products that are supposed to have some feature and fail to deliver on that promise.  It’s unlikely Seagate will allow this problem to spin out of control, the financial liability is simply too high for them (we’re talking about potentially being forced to repurchase almost every drive they’ve sold for the past three years AT THE PRICE THE CONSUMER PAID for it if they don’t fix the problem soon.

You can view more details in the knowledge base article below, and subscribe to updates.  You can also view many rants on these issues by doing a web search.

Originally posted 2009-01-22 01:00:02.

Promise NS4300N NAS (Update)

Looks like Promise has “fixed” the issue with Seagate 1.5TB drives in the NS4300N NAS…

They’ve replaced Compatibility List NS4300N_SR5_Compatibility_List_v1.0-20081031.pdf with NS4300N_SR5_Compatibility_List_v1.0-20081126.pdf on their support web site — the never revisions of the V1.0 Compatibility List omits the Seagate 1.5TB drive (interesting that they choose to call it V1.0 rather than V1.1 and remove the previous V1.0 list from their web page)… but the firmware release notes still contains the statement that they’ve added support for 1.5TB drives (the only 1.5TB drive I know of is the Seagate).

Promise’s actions are a little suspect… maybe it’s time for a trip over to Alameda’s Small Claims Court…  I’ve retained copies of both versions of the compatibility list as well as the firmware release notes.

And for the record, I have still yet to receive any update to my online support inquiry even though I’ve updated it a number of times with “additional” comments and information; and I’ve called Promise as well.

Originally posted 2008-12-04 22:13:22.

Computer Tid Bits

I haven’t sent one of these tid bit emails out in a long long time — this is just a collection of little points that you might find comes in handy.

Server 2008 is indeed out and available. I think I’m going to wait a few months (and I’m just about out of funds for MSFT store purchase, so doubtful I can get a copy for anyone else — I’ll probably do the MSDN OS subscription again). Hyper-V has not shipped as of yet.

Service Pack 1 for Vista can be downloaded or you’ll get it from Windows Update. If you’re updating more than a single machine, download the whole thing (Windows Update will swamp your connection). There are separate packs for 32-bit and 64-bit (you may need both if you have both machines). Also, copy the update file to the local disk (it will need elevated privileges to install).

Virtual Server 2005 R2 can be installed on XP, XP-64, Vista-32, or Vista-64. The management interface requires IIS, so that’s a little different with PWS version on non-server platforms. If you have VS installed on a server, you should be able to manage _all_ of your installations from one management interface (though Vista doesn’t make that easy).

Google GMail allows you to host your domains for email there for free… you basically get GMail accounts in your own domain. I’ve moved my mail services over there for the time being (I still archive all my email on my own server at home, but the active send/receive is done via GMail).

Parallels is coming out with a new server (64 & 32 bit) to compete with Hyper-V; I looked at the beta (definitely a beta, but useable), they may be able to get some of the market share — but my guess is they’ll get the share from VMware (I didn’t care for the Mac-ish look of the product on Windows).

2.5″ SATA disk drives continue to fall in price; Seagate 250GB drives were $104 @ Fry’s, and they still had some on the shelf on Monday!!!

Intel hasn’t release the most of the 45nm processor family yet; the older Core2 dual and quad processor continue to be a great buy. Remember that really none of the current Intel chip sets take advantage of the higher transfers the newer processors are capable of (well the X38, but that’s supposed to have major issues) — so you might want to wait for the next generation of Intel chips and motherboards to hit the market. FYI: Intel delayed the release because AMD missed their ship dates… their new cores had some rather serious flaws

Notebook and desktop memory are nearly on par with each other. You can purchase 2 x 2GB for under $100 (easily — even the really fast memory). $60 is actually the low price and $80 get’s you high quality with heat spreaders (notebook memory doesn’t have heat spreaders — no room). 2 x 1GB can be purchased for $40!!!

Originally posted 2008-04-01 12:58:23.

USB Hard Drive Adapters

 Everyone’s making them and they come in really handy…

 Basically they’re devices you can use to access a bare hard drive.  Most of them supports PATA and SATA 2.5″ and 3.5″ drives (though some vendors require a bunch of adapters to do it).  The APRICORN DriveWire unit is clean and simple and priced around $30 (use a price search engine) or less.

I was so happy to find these units that I purchased two of them and gave away my previous ones made by another vendor.

If you’re going to routinely swap drives on and off a computer, and don’t want to spring for an external case you might be better off with a hard drive dock also available for about $30, but they don’t support PATA (PATA is not hot swapable).

If you’re going to use these units to upgrade a computer’s hard drive, remember Acronis TrueImage is a great tool (you can find shareware and OpenSource tools as well — but TrueImage is well worth the price and has many additional features that you’ll likely find useful).

APRICORN: DriveWire – Universal Hard Drive Adapter

Originally posted 2008-12-29 12:00:32.

Vantec Quality

Before I left San Francisco I purchased six Vantec cases.

Two 5.25″ external USB2.0 cases for Blu-Ray ROM devices; and four 2.5″ external USB2.0 cases to put 500GB hard drives in.

I already had the Blu-Ray ROM drives and set out to put those in the cases right when I got them home from Central Computer, but I quickly found out that neither of the cases had the holes tapped for the bolts that held the case closed (and interesting enough, Vantec doesn’t shipped the cases closed up like most vendors).

It was a nightmare trying to deal with Vantec; they sent me two sets of bolts — they just never really could grasp the fact that the cases weren’t tapped — the screws were probably the right ones.  And even worse I’d already exchanged them once (and the second two cases also weren’t tapped).

Anyway, I gave up on trying to get satisfaction and just used some nylon fasteners that I had that seemed to do the job reasonably well — but of course the large white nylon fasteners sticking out the back of a black case was far from attractive.

The 2.5″ cases I packed away and didn’t need those (I actually had some SATA/USB2.0 cases that I was using at that point — but wasn’t willing to pay the ridiculous price to get more of those).

Last week, though, I ordered a couple 500GB Seagate drives on sale.  They arrived yesterday and I went to put them in the cases… The first package had the screw packet and worked great.  The second package didn’t have any screws and had a defect on the finish on the enclosure.  The third and fourth packages had no screws either.  So out of four drives only one had screws — and the screws are a small metric thread (and fairly long with a small diameter head) that I have nothing like.

I contacted Vantec; already knowing what they’d say… so once I dig up my receipt and send it to them I’m sure the fun will start again; the good news is I know that these cases are tapped (since I have two screws I tested all the cases).

It seems to me that Vantec has some rather severe quality issues; and simple things like insuring screws in the package that fit would be resolved by closing the case before packing and shipping it… obviously they want to save a nickle or so — and cost their customers hundreds of dollars in wasted time.

So I’ll not be purchasing any products from Vantec mail order for sure; and if I want to chance it, I’ll open up and inspect the item BEFORE leaving the store.

Originally posted 2010-01-30 01:00:58.

Online Capacity Expansion


  • Call me old fashion…
  • Call me conservative…
  • Call me a doubting “Thomas”…
  • Call me tickled pink…
  • Call me surprised…

I just finished adding four additional spindles to one of my virtual hosts; when I originally built it out I only had four spindles available, and didn’t want to buy more since I knew I would be freeing up smaller spindles for it soon.

The first task was to have the RAID software add the new spindles to the array, then to “expand” the array container… the first step took only a few moments, the second step took about 20 hours for the array controller to rebuild / expand the array.

The second task was to get Windows to actually use the added space by expanding the volume; to do that was a simple matter of using diskpart.exe (you can search Microsoft’s Knowledge Base) only took a few moments.

The incredible thing about this was that my virtual host and virtual machines was online for the entire 20 hours — with absolutely no service interruption.

This particular machine used a Dell / LSI controller; but the Promise controllers also support dynamic capacity expansion as do 3Ware controllers.  I believe the Intel Matrix pseudo RAID controller also support dynamic capacity expansion; but as with other RAID and pseudo-RAID controllers you should check the documentation specific to it and consult the manufacturer’s web site for errata and updates before proceeding.

The bottom line is Windows and RAID arrays have come a long way, and it’s quite possible that you will be able to expand the capacity of your array without taking your server down; however, if the data on the server is irreplaceable, I recommend you consider backing it up (at least the irreplaceable data).

Originally posted 2008-12-01 12:00:56.