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Using USB Hard Drives For Disk Images?
anomaly asks: "I work for a fairly large company, and we're faced with the problem
of maintaining images of hard disks for the hardware we use in our environment. We use Norton's Ghost for this process. We'd like to use a USB hard disk (because both the desktops and notebooks have USB interfaces) to store hard disk images, but Ghost requires DOS drivers in order to work. Does anyone know of a way that we could store, edit, and organize hard disk images as well as potentially installing the disk image via USB, or over a network? I suppose ideally we'd have some reliable, cheap network attached storage device (preferably in the $200-$500 range) - reliable in that we want to do 0 maintenance on these babies - so that many different hardware images could be stored and reinstalled as necessary. Any ideas?"
First off, I think you've made a number of incorrect assumptions. My views are based on years of corporate experience, including PC rollouts. Please read my responses below. Understand that I am the only person who gave you an useable, DOS/real-mode solution. And it's not as expense as you think.
So are mine! You think I've been fired for buying SCSI all these years? More $$$ does NOT equal quality. I go through specific products below ... (and note that NONE say "Adaptec" -- been burnt by their crap too many times).
All of the cards I use have quite stable drivers. Of course when you buy something new, you shouldn't expect it to work. You should always wait ~6 months for the bugs to clear out. But when if you'd waited 5 years for good Adaptec Linux drivers, then you'd get quite irritated.
You can easily standardize on one SCSI chipset, the TekRam TRM-S1040:
We cannot afford to put a Zip, Jaz, CD-R/RW and DVD-RAM/RW drive on every PC in my office. Instead, we have one or more external ones and put a $15-20 TekRam DC-315U in each system. Works great! Also great for cloning when I don't want to hit my server/network too hard (in the middle of the day), let alone transfer loads of data between systems. In Linux, I can even load/unload the TekRam S1040 driver on-the-fly, flipping drives on/off various systems without a reboot/shutdown. It's _awesome_ bay-bee!
As far as other experiences, I recently had to chuck my Adaptec AHA-2940UW (AIC-7880) in my Linux server because it is a POS (in 6 years of using Adaptec on Linux, I have yet to have a good experience thanx to their non-direct support). The sucker refused to work properly with a new, $4,000 Exabyte Mammoth2 60/150GB tape drive (talk about "betting my company's business" on a SCSI card!). I replaced it with an $60 Advansys (now owned by ConnectCom) chipset-based card:
But if you need faster still, Symbios Logic (now owned by LSI Logic) is always faster and more ubiquious than Adaptec. So much so that Adaptec attempted to buy Symbios out (since they were kicking Adaptec's butt in the OEM and FibreChannel market). You'll be interested in the popular 53c895/1010-series:
And when it comes to hardware RAID, Adaptec is just NT/Netware-only. As such, I prefer DPT or, better yet, StrongArm ASIC-powered Mylex RAID controllers with broad OS support (and better performance too).
So what brand are you blindly putting your faith in? Eh?
And those IDE drives can be put in a $20-40 enclosure and made to work at 20MBps+, right? Not! When it comes to external (isn't that what we are talking about, eh?), IDE is a joke -- with slow as molassas USB (even in 12Mbps/1.5MBps "fast" mode) being the only option (although new ATAPI-to-FireWire bridges, like this Ultra33 one from Intito, is changing that -- although it requires OEM firmware/programming). Plus we're back to the DOS/real-mode issue (even for FireWire). Only SCSI is "ready-to-go" external.
Now you can compare GB/$ all you want. You do NOT need the latest SCSI drives. Go with a late-model 9-18GB SCSI drive. I mean, how much storage do you need? We're only talking $100-200 for the drive, another $20-40 for the enclosure and another $10-30 for cabling and termination, max. You could do it for under $150, including cables and termination, if you pinch your pennies (and buy your stuff mail-order -- use Cyberguys for SCSI cables/terminators). Plus, you must be looking at 7,200-10,000rpm RPM drives -- don't make the mistake of comparing 5,400rpm IDE drives to obviously much faster SCSI drives.
-- Bryan "TheBS" Smith
-- Bryan "TheBS" Smith
Independent Author, Consultant and Trainer
Hi,
/. community excuse me, I'm going to talk about solutions that I know of, using Microsoft-based OS's.
.db file to store the users input then creates the .ini file from the .db).
May the
Multicasting :
You could create DOS boot disks with network drivers and TCP/IP then launch Ghost and do multicasting from a Ghost server which stores the images.
Ghost server runs on NT, I don't know if there are other versions available. Basically you tell it what image file to use and a few parameters (session name, number of clients...).
There you have your network attached device which stores the images. The hard part of it is getting boot disks that work with the NIC's you may have. This can be troublesome with laptops. Either have one disk for each NIC, or tweak and do a little programming to allow a selection during the boot process (I got one such disk that Does 3Com 5x9 and 9x5).
The same applies for IP addressing : you could have a disk that asks you the IP address and subnet you want to work with (Again, I got a disk that does that, it uses a
The most important benefit of this multicasting thing : network bandwidth is not wasted sending the same data many time over the network... You can Duplicate a disk on n machines at the same time with only one multicasting session.
Another solution is to create a boot disk with TCP/IP or another NetBIOS enabled protocol (NetBEUI or IPX/SPX) and connect to a network share on a NetBIOS server (could well be a Linux/Samba box), on which you have your images. Down side : each copy requires the data to be sent from the server to the station, thus using a lot of bandwidth.
As for USB, I have no idea how to configure these things under DOS...
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Katchina'404 explanation was very good I'd just like to add a couple of things. CATC has drivers for usb under dos http://www.catc.com/products/usb4dos.html Probably costs a hefty penny and I doubt will fit on a normal floppy. And for the network bootdisks as mentioned before http://www.bootdisk.com has a variety of network bootdisks. Most of them use Microsoft Lanman for DOS.
I've said it before, and I'll say it again. At only $15-20 extra per machine, you should be buying systems with SCSI cards. After that, you can plug in external SCSI devices, like hard drives, that are 20x faster than USB with full DOS/real-mode compatibility.
For more information, see this previous /. thread on USB hard drives (and just how freak'n slow they are). Look for my post in the middle (search for SCSI).
Otherwise, does anyone know if IEEE1394 FireWire cards have ASPI/real-mode drivers? If so, that might be another good option. But since most PCs still do not come with FireWire, and FireWire cards are more expensive than SCSI (and the drives aren't much cheaper, although Maxtor is trying to change that), it may not be better.
Either way, avoid USB since it is a slow pig. SCSI or FireWire is a much, much better angle that is 20x faster!
-- Bryan "TheBS" Smith
-- Bryan "TheBS" Smith
Independent Author, Consultant and Trainer
Scripting is great. It simplifies life tremendously.
Another thing is that it's possible to edit ghost images - something I don't think is possible with dd.
Mount via a loopback? Would probably have to decompress the image first, but as long as there's a supported FS in the image, shouldn't it work?
--
"The urge to save humanity is almost always a false front for the urge to rule." --H.L. Mencken
We burn the images to bootable CD's or we have a bootable CD that pulls the image across the network. We tried using the external drives but found that it wasn't as convienient or as fast as carrying a couple of CD's around. Besides, we always have our CD cases with us.
Is there anything that this Ghost does that couldn't be accomplished using, say, dd? I've played a bit with dd+netcat+gzip for creating disk images, and everything *seems* to work ok (I seem to recall being able to send images over a network, but I don't remember if I ever got around to mounting them via loopback or whatever to check that they were usable).
Assuming Ghost doesn't do anything really funky to the disk images, perhaps a modified tomsrtbt (2.2.18 kernel) or somesuch would be a solution. You'd also theoretically be able to access Zip (etc) drives to pull off images as well.
--
"The urge to save humanity is almost always a false front for the urge to rule." --H.L. Mencken
I tried to make this an Ask /., but alas, it was rejected.
I'd like to back up every bit of several HDs I have. (I do not intend on forensic recovery... no new hardware) I THINK there is a way to use dd for this, but I'm a little new to it... I'd like to be able to grab absolutely the entire contents of the disk, including the MBR, partition table, etc., and including any "deleted" files or non-overwritten sections of partially overwritten files.
I'm also interested in preferences regarding compression. I know it will not be terribly effective (the biggest gain is taking out the fs space...) but even a small gain would be useful. I also want to avoid any compression scheme which destroys an archive due to small early errors, like gz (as I understand...)
thank you
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I used to store our images on our NetWare network, boot from a floppy, and Ghost them down. But I finally realized I saved a lot of time just storing all the images (we use about 10) on a 20 Gig IDE drive, popping the cases off the systems that need the image, and Ghosting from a Win98 boot disk. Takes between 5 and 10 minutes compared to 20 to 40 minutes over the network. I guess I just don't mind sticking my hands in the guts...
We use DOS network boot disks with scripts which automatically set the IP and then do a simple "net use X: \\server-name\sharename". The X: drive shows up in a list of drives in Ghost; all the stuff gets imaged right to the network drive. Don't even need a Ghost server.
- A.P.
--
* CmdrTaco is an idiot.
"Remember when the U.S. had a drug problem, and then we declared a War On Drugs, and now you can't buy drugs anymore?"
Secondly, the TekRam DC-315U is a measly $15-20, does UltraSCSI (20MBps) and interfaces nicely to just about any old/new hard drive. It is completely supported by just about any OS (TekRam even has Linux and BSD drivers -- including distro installation driver disks). I buy one for all new PCs I get -- a smart move given the number of external Zip, Jaz, burners and whatnot that fly around the office.
Third, you can get late-model SCSI drives for under $100. Most will have enough storage for several cloned images. You don't need a modern SCSI drive, just one that will give you about 15MBps performance -- that's 10x the performance of USB!!! Add $20-40 for an external case, another $20-40 for cables and terminators and you're cooking! If you use Linux, you can hot-plug the solution and modprobe the TekRam driver on-the-fly!
Fourth, I do this for cloning. Yes, I do some over the network, but I don't always like to taxi my server in the middle of the day (among other reasons). And if I need to get the system up faster, SCSI gives me better performance than the network. Either way, USB is a slow pig and anyone who has used an external USB knows what I'm talking about! God, I cannot believe people have such ignorant, "say no to SCSI" attitudes! Geez!
Fifth, I'm glad someone else mentioned (since I forgot to) that PCMCIA SCSI cards are easily swappable, so yes, I use a PCMCIA SCSI card for the few notebook systems I have. I only need one card (and I have only one card).
Six, I do NOT disagree that IEEE1394 is a better, future solution. Frankly, I'm PO'ed that Intel is stalling on making it a standard feature in the southbridge chip (it was supposed to be standard with the PIIX4 southbridge!). I think AMD/VIA will force the issue with forthcoming chipsets and that will finally force Intel to put it on-board as well. Until then, TekRam SCSI cards are half the price and almost as fast (20MBps) as the 100-400Mbps (12.5-50MBps) Firewire cards. And, again, I'm NOT sure there is DOS/real-mode support.
[ But it's still good to see companies like Maxtor coming out with IEEE1394 drives (probably using a 33MBps 1394 to ATA bridge like this one). ]
-- Bryan "TheBS" Smith
-- Bryan "TheBS" Smith
Independent Author, Consultant and Trainer
FYI, I seriously doubt you get Ultra100 on a 100-400Mbps (12.5-50MBps) Firewire interface. In fact, all the ATA to 1394 bridge controllers I've seen are Ultra33 (33MBps -- like this one).
Most IDE/SCSI drives burst transfer at 15-30MBps from platter to interface. The 12Mbps (1.5MBps) interface of "fast mode" USB is a major bottleneck.
Worse yet is the massive overhead (much worse than SCSI or Firewire). USB is one of the worse serial busses ever created. There were better alternatives but Intel and Microsoft designed USB so most of the effort fell on the device and drivers (the controller and OS support is minimal). Why do you think the devices lacked the basic southbridge/OS support by 2-3 years???
-- Bryan "TheBS" Smith
-- Bryan "TheBS" Smith
Independent Author, Consultant and Trainer