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Mini-Ductor Induction Heater
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Review and Analysis
For the last year I’ve been involved with a start-up called Fluxeon, a company founded to manufacture and sell low cost induction heaters. (If you don’t know what an induction heater is, go here) Naturally one should be aware of his competition so we recently decided to take a look at the Induction Innovation’s Mini-Ductor hand-held induction heater. Going by the specifications, this heater competes head-to-head with our upcoming product, both price and feature-wise.
Another reason that I wanted to take a look at this unit is that I’ve been contacted by several potential customers interested in something that would do a better job. To be fair, their applications are outside the Mini-Ductor intended area which is automotive-repair-related.
So we purchased a unit and I proceeded to evaluate it, tear it apart and reverse-engineer it (but as will be obvious, not copy it). I decided to write this review to share my opinions with others.
Receiving
Here is how I received the unit. It is sturdily packaged in a foam lined plastic case. Included in the case are the heater itself, a nut heating coil, a flexible coil made of Litz wire that can be wrapped around things and a single strand wire that can be molded to any shape. Plus the usual warranty card and a fairly lame instruction manual, half of which is taken up by warnings. One can tell that the lawyers are in charge of this company because it has such creative warnings as not to wear anything with metallic buttons or zippers for fear that one might get burned! I kid you not.
Here’s the unit in my hand with the nut heater coil attached. This unit is much larger than it might appear in brochure pictures.
The body of the unit is a length of thin wall PVC sewer pipe. (OK, I’m just kidding about the sewer part but it IS plumbing tubing). The shroud around the power button is another machined PVC piece that is attached to the main body with cement. The power cord enters the rear through a drain grating inside which a fan resides. On the other end are two “D” shaped pieces of either copper or brass with standard electrical lugs soldered on. These lugs receive the work coils.
The “D”s are held to the PVC pipe with 4 large sheet metal screws. When the unit is on, these screws are “hot” with RF energy. It’s possible to get a little RF burn by touching the hot D with a sweaty finger.
First Test
Naturally the first thing one wants to do with an induction heater is to heat something So I cut the head off a half inch bolt and proceeded to heat it.
After about 20 seconds this is what I got. Frankly I was not impressed. The company rates the heater at 1000 watts. They don’t specify so I assume that this is input wattage drawn from the power line.
The Fluxeon 1kW induction heater will almost melt this bolt. It heats it to a brilliant white heat with little sparklies coming off. This is NOT a 1kW heater.
The next step was to see what the heater is really doing. So I got out my trusty old Kill-A-Watt. I have previously compared this meter to lab standard watt meters and found it to be accurate to the watt. So I plugged the Mini-Ductor into the KAW, placed the bolt back in the coil and…
What the KAW read. It only read this value for an instant. After that the power ramped down steadily as the work coil heated up and its resistance increased. It ended up around 400 watts.
Interestingly enough, and just the opposite of the behavior of most induction heaters, this heater actually drops power when the ferrous metal goes through the Curie point. Most heaters, if they don’t have Automatic Power Control increase their power input after the Curie point. This is a function of the electrical architecture of the unit. More on that later.
Seeking Power
Needless to say, I’m was not impressed. So I started looking for that missing power. One obvious limitation would seem to be the work coil. It is made out of tin plated, approx AWG 10 wire. A heavier coil would have less resistive losses and thus should transmit more power.
So I dug out one of the helical coils that I wound for our heater, brazed smaller tubing to it so that it would fit the electrode attachment fittings and tried it out.
Not so good. In fact, just the opposite of what I expected. A possible reason might be that this coil is slightly larger in diameter than the nut heating coil supplied with the Mini-ductor.
The manual says that the more turns over the work, the more heat is produced. Sounds reasonable so.
I would a coil out of very heavy gauge Litz wire. I figured that the Litz wire, having lower resistance to RF than regular wire, would give the heater every possible advantage. Unfortunately…
Even worse. Again, part of the problem may be with the diameter of the coil. I didn’t have anything handy to wind a smaller coil onto but based on my work with other heaters including the one that I designed, the minor difference in diameter should not have made much difference. In fact, my heater actually transmits more power to that same bolt with a work coil this size.
At this point, I had to reach the inevitable conclusion that the company is advertising this heater as something it is not. I can’t imagine any way of loading this heater that would cause it to draw a kilowatt from the line. Will it do the job that it’s intended for? Probably, if you’re patient. Is it truth in advertising? Nah.
Peeking Inside
The performance testing out of the way, it was time to look under the covers, so to speak. Opening the unit is trivially easy. Just pop out the 4 screws holding the “Dees” in place, remove and unhook the power switch and shake out the guts. They are not held in place by any fasteners. Just slid into the sewer pipe and roughly affixed by the stiff leads going to the “Dees”.
Here is a view of the business end of the guts. On the left are the two “Dees” that the work coil attached to. In the center is a ferrite-cored transformer and on the right is one end of the printed circuit board (PCB).
Here are some more views of the PCB. The big orange capacitor is the tuning capacitor that resonates the transformer primary.
Note the highly optimistic 12 amp fuse!
In this view the little cooling fan can also be seen. Interestingly enough the fan is powered by a single loop of wire looping through the transformer core. I imagine that was cheaper than dropping the line voltage down to the 12 volts that the fan requires.
The architecture of this heater is what is known as a current fed push pull transformer architecture. A functional diagram is shown at the left.
The high voltage DC from the line voltage rectifier comes in at the top and feeds the center tap of the transformer through the current feed choke. Each half of the transformer primary is fed by a power FET. When one FET is on, the oher is off and vice versa. This is known as “push-pull” drive.
Here are the actual transistors. This is something that I really don’t like. They are simply glued to the aluminum heat sink using a thermally conductive glue. The glue is quite brittle – it easily flakes away at the light touch of a screw driver tip. Thus one could anticipate that these transistors could come unglued, perhaps when the unit is dropped, and subsequently over heat.
The choke can be seen here, nestled inside the aluminum angle iron heat sink. It is not attached to anything other than by its leads and presumably a little pressure from the angle iron so it is subject to vibrating or being jarred loose.
I can understand the company trying to hit a price point but this use of glue and cable ties to hold the assembly together does not sit well with me. It certainly does not look mechanic-proof
This is the resonating capacitor. It is appropriately sized and rated but again, it’s just hanging by its leads. Not even glued down.
Now to the heart of the unit, the transformer. This photo shows several features. The red arrow shows two things. One, a small air gap to prevent the core from saturating and two, that the two core halves are offset. In fact, this core is held together only by that white tape. It is usual practice to affix the core halves with cement to make sure that they don’t come loose. That wasn’t done here. Just some tape that can loosen with heat and age.
The green arrow shows the center-tap lead entering the primary. The blue arrow shows the two Litz wire primary leads.
Here is some detail of the transformer with the outer tape peeled back. Pretty standard construction. The primary is next to the core and the secondary is the single layer of heavy Litz wire on top. Under the white tape is the single loop that powers the cooling fan.
Again here, tape is used to hold things together instead of cement or mechanical fittings. Still seems not mechanic-proof.
Here’s a look at the secondary. If you look closely you’ll see that the secondary is actually two Litz wires in parallel. There are 5 turns to the secondary.
Next we come to the “Dees”, the part of the machine that anchors everything down and receives the work coils.
In this view you can see the Dee itself and the standard electrical lug (red arrow) that is soldered to the Dee. You can also see where the Litz wire is rather sloppily attached to the Dee (green arrow)
Outer view of the Litz wire attachment. Again, the use of tape where something more substantial would seem appropriate.
Electrical Analysis
The next step in my evaluation was to connect an oscilloscope to the unit and see what I could see.
Here is the voltage across the work coil. It is a nice, low distortion sine wave, what I like to see. What I don’t particularly like is the envelope. That is, waves of all different amplitudes, represented by the filled in area under the curves. Let’s see why that is.
Here is the current waveform with the scope time base turned down enough to see the 120 hz envelope. Each envelope is a half wave of the full wave rectified 60 hz incoming current.
For some reason they chose not to filter the rectified DC. The result is a lot of power opportunity wasted. The peak current in the primary is about 30 amps. If the rectified DC had ben filtered even a little, all or part of that un-lit space between the envelopes would be lit. That represents lost power. With good filtering, the screen would be lit solid across the waveform. That would represent the maximum power that could be produced for a given peak current. Perhaps there wasn’t room for a capacitor in the sewer pipe or perhaps an electrolytic cap cost too much. Whatever, this is where some or all of that missing power has gone to. I imagine that the power at the peak of the waveform is at least a kilowatt but the RMS value, what does the heating work, is much less, probably half.
This is the voltagewaveform at the lower side of the current feed choke. Pretty typical for that kind of feed.
Here is the voltage waveform on one of the FET’s drain leads. Again you can see the envelope produced from the unfiltered 60 hz power.
Conclusion
The first question on many peoples’ minds is “Is it worth the money?” At about $400 street price, it’s a close call. It will probably do most of the things that it is advertised to do. That is, it will heat stuck nuts and bolts and will work out dents in sheet metal and release adhesive holding things to metal. On the other hand, it is a very cheaply made product that probably will not withstand the rigors of shop use. I can imagine the results of a few drops onto concrete floors, especially in cold weather when the plastic gets brittle.
One thing that this heater is NOT is a general purpose induction heater. As we found out, it can’t heat neon electrodes. In fact, that deficiency is what started us on the Fluxeon path. <shameless plug> The heater that we will be introducing in a couple of months is a general purpose heater. It will initially be rated at 1000 watts but in reality, that is the minimum power that it’s capable of. It will do significantly more in typical situations. Tape and glue will not be structural elements either. </shameless plug>.
Stay tuned to this space for updates and occasionally check in on http://www.fluxeon.com. The site isn’t live yet but it will be soon.
John
Posted by neonjohn on January 8th, 2010 under Electronics, Induction heating, Science |7 Comments » :::del.icio.us :Digg it :StumbleUpon :Yahoo MyWeb ::
The Linux Chronicles – WD MyBook NAS Storage
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With just a little over a TB of storage on-hand, things were getting kinda tight (who’da thunk that 5 years ago?) so I decided to buy some storage. To reduce the number of connections to my computer, this time I wanted Network Atached Storage. NAS is really a small computer and drive combo in a nice little enclosure. It usually runs Linux and when attached to the ethernet, becomes another network file server.
I looked around and decided that the 1TB Western Digital MyBook World Edition would be a good option. I’ll tell you right up front that if I knew then what I know now, I’d have spent the extra money for the MyBook World Edition II. This box contains two drives arranged in a RAID configuration. The data is stored redundantly on both drives. If one drive fails, simply remove it and replace it. No data lost. Oh well, I got the Edition I and this is a review of that device.
Amazon had it on sale for just a touch over $100 so I bent the plastic and got one. It arrived complete with ethernet cable and wall wart. That’s my only minor quibble. The wall wart takes up a lot of room on the outlet strip. I wish they’d used a power brick with a cord like most computer accessories do today.
I plugged it in, attached it to my router and it came up immediately. For my winders software development machine, attaching the drive was just a matter of running the setup disk. Some PFM happend and it showed up as drives Y and Z.
This brings up the next thing that I don’t like about the drive. It comes divided into 2 shares called Downloads and Public. These are not removable. Fortunately the whole drive is available to either share so it is more a nuisance than a show stopper.
Setting up Linux is a bit more involved. I’ll outline the process here. Any device on a network has to have an IP address. The MB comes out of the box set up to get an address via DHCP. In my case, my HughsNet modem is the DHCP server. The drive got assigned the next available address in the 192.168.0.x space. That’s fine on a pure windows network but Linux and NFS (Network File System) really need a static address. So the first thing to do is to change the drive to static addressing.
The first step is to fire up your browser and log onto the built-in web server on the drive. Simply enter http://192.168.0.x, replacing X with whatever number was assigned the drive. You may have to try a few to get the right one. If your network is small, x is likely to be 2 or 3.
Log in using “admin” as both the userid and password. Click on the “Network” icon. Click on the drop-down and select “static” for network node. Since DHCP assigns addresses from typically 2 (1 is reserved for itself), convention is that static addresses be assigned from 254. On my system, my router is 192.168.0.254 so I assigned my drive the address 192.168.0.253. Note: some LANs use the private IP address range of 10.0.0.x. If yours does then substitute that for the 192.168.0.x in these instructions.
Now some sleuthing must be done. You need to know your gateway to the internet and your DNS servers. The gateway is normally your broadband modem which usually has the address 192.168.0.1. On a windows system, the easiest way to find out both the gateway and the DNS servers is to click on the network icon in the tray and follow the prompts to that info. Sorry I can’t be more specific but I don’t do winders :-)
My gateway is my HughsNet Satellite modem at 192.168.0.1 and my DNS servers are 67.142.160.8 and 67.142.160.9. Do not use these! They are specific to my installation. Use either the DNS addresses provided by your ISP or a public server such as this one.
OK, we have a static address assigned so now let’s make the drive available to the linux system. With Ubuntu, convention is that external drives are mounted in /media.
The first step is to open a shell window (Applications->Accessories->Terminal) and execute the command
$ cd /media
Then execute the following commands
$ sudo mkdir public
$ sudo mkdir download
This creates two mount points. next, execute these commands
$ cd /etc
$ sudo gedit fstab
/etc/fstab is the place where all drive mounting information is stored, including network drives. Once in the editor, add these two lines:
192.168.0.253:/nfs/Public /media/public nfs
192.168.0.253:/nfs/Download /media/download nfs
Substitute the IP address of your MB if it is different from mine. Save the file and exit the editor. Now execute this command
$ sudo mount -a
This tells mount to mount all the drives listed in the /etc/fstab. Mount normally works silently so if you get nothing other than a command prompt, you know that it worked. Eror messages must, of course, be addressed.
Now when you click on Places, you’ll see two new places, “public” and “download”. See, wasn’t that easy? The two shares should mount automatically during boot but if they don’t, simply open a shell and execute “sudo mount -a” again.
The Downloader
One of the neat features of this drive is the downloader. Through the clunky web interface, you can start a download directly to the WB and then turn your computer off if you wish. Very nice for getting those new Ubuntu ISO releases. It can do both HTP/FTP and BitTorrent. The downloader contains a scheduler so I can, for example, set it up to only download during my quota-free hours in the early morning.
To access the downloader, log out of the drive’s web interface if you’re in “admin”. Enter http://192.168.0.x into your web’s browser as before. Select “downloader” from the drop-down menu. This time enter “downloader” as both the userid and password. Then just follow the simple prompts. The only minor negative is that you have to locate the URL of the download in your browser and then cut and paste that address into the downloader menu. A plugin for Firefox that intercepts clicks and fires off the downloader would be nice. We can always wish…. :-)
The Good Stuff
The good stuff is the embedded Linux system. Fortunately WD responded to user requests and made the shell easily accessible. Having the root shell means that you can hack the system or just play around and learn Linux. Always been interested in Linux but didn’t want to buy another computer? For just over $100 you can get a Linux machine with a 1TB hard drive attached!
The first step is to enable SSH (Secure SHell) on the MB. Log into the admin web interface and click the Advanced button at top and then click the “Advanced” button. The first option is to enable root shell. Click the check-box beside “Enable”. Click “Submit”. There, you’re done.
If you’re on a windows machine, you’ll need an SSH client. I recommend Putty. If you’re on a Linux box then SSH is built in. Open a shell window as described above. Type the following command
$ ssh -l root 192.168.0.253
Using the IP address of your MB, of course. You’ll be prompted for a password. Enter “welcOme”. That’s an upper-case O and not a zero. You should get the normal # root prompt. From there you can do most anything that you could do on any Linux box.
WD has chosen to strip away some of the system such as the C compiler. Too bad. However, the hacker community has come to the rescue. Google “Hacking the Western Digital MyBook”. Note that the version being sold as this is written is the white light version. The blue band version is obsolete so don’t get sidetracked into trying to do hacks for it.
Incidentally, if you don’t want to use the clunky downloader interface, you can use the program “wget” directly. From the shell prompt, if you want to download to the /nfs/Download directory (where it will show up on your network drive), simply do the following
# cd /nfs/Download
# wget <url of the file to download>
If you want to duplicate the functionality of the downloader that lets you start a download and then go to bed, use this command.
# nohup wget <url> &
Nohup tells the system not to kill the process when you log out and the “&” on the end puts the job in the background. You’ll notice a number in square brackets like this [1] when you execute the command. That’s the job number. You can bring the job back to the foreground with the command
# fg 1
If you forget the “&”, a ^Z will put the job in the background. The process stops the job so execute
# bg 1
to restart it.
External Drive
The MB has a USB port where you can connect an external drive. This drive can be used to back up the MB or it can be mounted as another network drive. In windows, when the setup utility is run, the external drive shows up as drive X:.
For some reason the MB comes configured to disable NFS on the external drive. I prowled around the system for awhile and determined that I’d have to hack system files to enable it. This would FUBAR any future firmware upgrades so I decided not to.
Fortunately the drive can be mounted as a microsoft network drive using SAMBA on the Linux machine. Ubuntu comes with SAMBA installed so only two things have to be done to mount the drive. Create a mount point and edit /etc/fstab. Here are the commands. I called the mount point 1tb because the external USB drive that I bought at the same time is also a 1Tb drive. Open a shell window on your Linux system.
$ cd /media
$ sudo mkdir 1tb
$ gedit /etc/fstab
Go to the bottom of the file and enter this line
192.168.0.253:usb1-1share1 /media/1tb smbfs
“usb1-1share1″ is what the MB’s linux system mounts the external drive as. It is mounted in /nfs but you do not enter a path in the mount command for the microsoft network like you do for NFS. Save the file and execute
$ sudo mount -a
You’ll see “1tb” show up in “Places”.
File Copy
The last facility that is built into the MB is a file copy utility. This allows you to copy files to and from the MB and the external drive without the data having to travel over the network. The copy is VERY fast.
To access this facility, log into the web interface as before. Enter “admin” as the userid and password and choose “Copy Manager” from the dropdown menu. Then follow the prompts.
A very handy use for this facility is to back up the MB onto the external drive. It can also copy to and from thumb drives and portable drives. Unfortunately it can’t download from cameras. I don’t understand why since Ubuntu has that ability.
Well, that ’bout wraps it up. Oh, before I forget, here’s my setup. I like the contrast between the new and the old (dial phone and converted oil lamp). Everything on that table runs from a large UPS in my basement, as does my computer so I’m immune to the daily power drops and chugs that goes with living in the mountains.
Oh, before I forget #2, change those password! Since your drive is sitting on a network accessible to the world, it is subject to being hacked. leaving the default passwords is practically a guarantee. You can change some of the passwords from the web interface but you can change them all from the root shell prompt and do so much faster. SSH into the MB. Then use the following commands.
# passwd root
# passwd admin
# passwd downloader
Then you can enter the new password. You may use the same password for all three.
Enjoy,
John
Posted by neonjohn on December 22nd, 2009 under Computing |Comment now » :::del.icio.us :Digg it :StumbleUpon :Yahoo MyWeb ::
The Linux Chronicles – One Year Anniversary
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Can’t believe how long it’s been since I’ve posted. I’ve been very busy on my induction heater project plus I’ve had the mother of all writer’s block. Plus, Ubuntu has simply worked so I haven’t had much to write about. Anyway….
I’m approaching my one year anniversary of my conversion to Linux after (mostly) giving Windows the boot. I thought that it would be a good time to upgrade and post about it.
I had stayed with Ubuntu 8.09.1 Long Term Support because I thought that it would be more reliable than the non-LTS releases. That was a mistake for two reasons. One, Ubuntu is reliable, period. Two, I didn’t realize that when I did upgrade, I’d have to go through all the intermediate steps in the process. Another reason to upgrade is that a given release generally does not upgrade packages. Thus I was stuck with Firefox 3.0 even in the face of the much superior 3.5 release.
So, a couple of days ago I went here and downloaded the ISO of release 9.10 and burned a CD. After doing an image backup (see previous posts on how to use partimage to do that), thank God, I started an install. I figured that it would detect the old version and do an upgrade. Wrongo! It installed right over my old version.
After restoring from my backup, I actually read some instructions. It turns out that I had to do an upgrade and not an install. To do so, go into the system->admin->Software Sources, click the “Updates” tab and select “Normal Releases” at the bottom of the window. Then when I run Upgrade Manager, it presents me with the option to upgrade to the next release. Like I said, each release has to be upgraded to the next, one step at a time.
I downloaded the older release ISOs and mounted them, thinking that it would speed up the upgrade process. I don’t think that it did. If you have a decent internet connection (my HughsNet at 1.4mbps is barely decent), the network upgrade is the way to go.
Fire off system->Administration->Update Manager and click on the “new release” icon at the top of the screen. Get a good book, sit in front of the computer and kill about 4 hours. This brings up my only real beef with the upgrade process. All through the process it asks questions, some of them definite guru questions, so that you can’t just go off and let the upgrade run overnight or something. It seems like the upgrade could be arranged so that it asks all the questions at the first or at the end of the upgrade. Speaking as a complete upgrade novice, of course.
So I upgraded to the next release, rebooted into the LiveCD and did a partition backup of the new root drive. Then reboot into the system, fire off Update Manager and repeat the whole process for the next release. Mainly because I have to wait until my Hughsnet download quota is suspended (2-7AM every night), it took me the better part of 3 days to get the updates done. I will NOT fall behind again.
So how did the upgrades themselves go? Almost completely painlessly. The only tiny little snag was that the last upgrade to 9.10 trashed a few of my desktop icons. BFD! In the microserf world, try upgrading from say, Win98 to System 7 and see what happens. You’ll spend the next week (or more) working out incompatibilities and fetching new software (having to pay for a lot of it) because the old stuff will no longer work. One of the reasons that I held back for so long on the upgrades was my experiences with microserf’s crap. I should have known better, that the Linux/Ubuntu process would be flawless.
One Year and Counting
My Linux experience has been wonderful. It took awhile to get used to the Linux Way but after that, I’ve been right at home. I can do almost everything that I could using winders. For those few instances where a Winders package simply can’t be replaced, there’s Sun Microsystem’s Virtual box. VirtualBox, which is free, lets me boot winders in a window on my Linux desktop. Windows runs as just another task. And when Windows crashes, simply close the window and you’re done with it.
I installed the version of Windows that came with my old Dell laptop. It was supposed to be bound to that hardware but VirtualBox takes care of that. It runs very smoothly – as smoothly as windows can. In fact, I’m writing this post using a nice little program called BlogDesk that is running under XP in a desktop window.
Now I have the best of both worlds. The reliability and flexibility of Linux and on the rare occasions when I need it, Winders is just a mouse click away. And like a rabid dog, winders is properly caged in its own environment where it can’t cause harm to the actual system. I like that.
In summary, the conversion to Linux has been a complete success. There is very little more that I could ask. The system just runs. The only time that it gets rebooted is when an update calls for a reboot.
John
Posted by neonjohn on December 22nd, 2009 under Computing |Comment now » :::del.icio.us :Digg it :StumbleUpon :Yahoo MyWeb ::
The Linux Chronicles – Making Backups
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This post is about backing up. More specifically, backing up in a way that is usable. That is, that precludes your having to do a full re-install if something happens to your disk.
In the linux world there are two kinds of backups:
- File oriented
- Partition oriented
File oriented backup simply means that you copy all your files from one place to another, “another” being another hard drive, a network drive or some other type of storage like DVDs. Partition-oriented backup means that you back up the whole partition. This gets the OS, all the files and everything else. This is similar to drive cloning in Windows
Critical to either backup method (unless you like swapping a LOT of DVDs) is a large external hard drive. By large I mean at least 400 gig. External USB interface hard drives are everywhere these days and are dirt-cheap. I got my 400 and 500 gig drives from Sam’s Club. They seem to always have the cheapest price at the moment when shipping is figured into alternatives.
Equally critical to success is to have a backup plan. A plan is not “I’ll backup whenever I think of it”. A plan is a method and automation to do it on a regular and fail-safe basis. A good plan might be “do a partition backup once a week and daily incremental file backups.”. In fact, that is my plan.
A root partition backup can’t be automated because the partition must be unmounted which isn’t possible for the partition that was booted. Therefore I have my Palm Pilot set to remind me to do a backup every Sunday evening. Daily incremental backups are automated.
Daily Backups
The solution for daily backups is simple – “Backup-manager”. This program is in the repository. Simply start the Synaptics partition manager from the desktop and search for “backup-manager”. Check it to be installed and let it download and install.
There is a tiny bit of setup to be done. There is a file called /etc/backup-manager.conf that must be edited. This might seem daunting but it isn’t. Simply open a terminal window from the desktop and execute the following:
$ sudo vi /etc/backup-manager.conf
if you’re comfortable with vi or
$ sudo gedit /etc/backup-manager.conf
if you’re more comfortable with a windowed editor.
The first thing to change is the destination. This will be your external hard drive. When the hard drive is plugged into a USB port, it automatically mounts in /media using the volume name that it is given. I changed my drives’ volume names to something more descriptive than “segate xiys-4958773″ or something similar. Descriptive names like “400 gig” and “500gig”. Therefore my 400 gig drive mounts as /media/400gig.
On that drive I have a directory for backups called “Linux_Backup”. So the destination for backups is “/media/400gig/Linux_Backups“. Remember that case matters in Linux so get your capitalization correct.
Back to the config file. At the top of the file you’ll see something like this:
############################################################## # Repository - everything about where archives are ############################################################# # Where to store the archives export BM_REPOSITORY_ROOT="/media/400gig/Linux_Backup"
Simply edit the text inside the quotes to match your destination.
Got it? Good. We’re a third of the way done. Next, go down to where you see this:
# The backup method to use. # Available methods are: # - tarball # - tarball-incremental # - mysql # - svn # - pipe # - none # If you don't want to use any backup method (you don't want to # build archives) then choose "none" export BM_ARCHIVE_METHOD="tarball-incremental"
Simply edit BM_ARCHIVE_METHOD to be exactly as shown. What this means is that on the designated day of the week (Monday by default), a full backup will be made. On other days, only those files that changed will be backed up. That’s called an incremental backup.
Finally we specify what to back up. Find this section in the config file
# It's recommanded to use BM_TARBALL_TARGETS[] though. # Warning! You *must not* use both variables at the same time. # NOTE: The Debian package will only update BM_TARBALL_DIRECTORIES # Paths without spaces in their name: export BM_TARBALL_DIRECTORIES="/etc /home /usr /var /lib"
I strongly recommend backing up all the directories listed above. Just copy that line directly into your config file.
That all there is. Save the file and sit back and relax. Sometime during the day every day this program will run and will back up your stuff. The default is to keep 5 generations of backups. That’s why you need a large drive. You can edit the config file to change that number if you like.
See, that wasn’t difficult at all.
Partition Backups
Partition Backups are no more difficult but they are more involved. That is, more steps are involved. We’re going to use the program partimage that I’ve discussed before. IF you don’t already have it then fire off Synaptics Package Manager and get it. Just search for “partimage” and install it.
Partimage usually resides in “/usr/sbin/partimage”. For this task we need it to reside on the backup drive. Therefore we’ll copy it over. In these examples my backup drive is named “400gig”. Substitute the name of your drive.
Open a terminal from the desktop and type the following:
$ cd /mount/400gig $ sudo cp /usr/sbin/partimage .
That copies partimage into the root of the 400 gig drive.
Partimage can’t work on a partition that is mounted and subject to change at any time and yet we want to back up the root partition that contains everything in a default Ubuntu installation. The solution is to boot from the Live CD. That’s what we’re going to do.
Put the live CD in your CD or DVD drive, click in the red power symbol at the top right of your desktop and choose “restart”. Your system will shut down and will reboot into the live CD. Answer “English” (or your native tongue) and then choose “Try Ubuntu without changing your system” or something to that effect. It is the default option.
When the boot is finished and you have a desktop, open a terminal window and type the following:
$ cd /media/400gig $ sudo ./partimage
You should see a screen similar to this:
To move from field to field use the <tab> key. Use the <space> bar to make or unmake a selection. Notice where I filled in my destination file name. When you have your screen matching this, press <F5> to go to the next screen:
The important parts are:
- no compression. Unless you have a VERY fast processor, use no compresion. This program is capable of transferring data at the speed of the drives (over a gigabyte a minute). Compression greatly slows things down. It takes about 30 minutes to back up 50 gigabytes of data from my hard drive. That stretches out to hours with compression. We have a large backup drive so let’s use it.
- Check Partition Before Saving. This is very important and only adds about 5 minutes to the job. An unhealthy partition might not restore.
- …into files whose size is. This causes partimage to create a new file every 2 gig or so. This is very important when backing up to a windows formatted (NTFS) drive, as all USB drives come from the factory. NTFS gets very slow as a file grows past 2 gig. Probably a legacy from FAT32 days. Anyway, make sure this option is selected.
When you’re ready to start, press <F5>. Then go kill a half hour or so. When the backup is finished, reboot to your regular system and you’re done.
Restoration involves the same process except that you choose “restore a partition from an image file” on the first screen. The major benefit of this backup method is that it takes a snapshot of the system as it existed. A restoration puts it back exactly like it was when the snapshot was taken. No re-installing the system from the Live CD and copying files. No muss, no fuss. Just reboot and you’re up and running again.
Summary
To summarize, I use partimage to back up my root partition about once a week. Every day my machine is backed up automatically by backup-manager. Simple and clean. And reliable.
If you’ve ever done a backup under windows, you’ll really appreciate how much easier this is. Oh so typical for Linux. You’ll also notice that you didn’t have to spend any money on a backup program that uses a proprietary format and might not work when you need it to restore. I’ve been bitten by that one more than once. Partimage is open source and free and always will be. It will always work. Again, that’s the Linux way.
Posted by neonjohn on March 2nd, 2009 under Computing |
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