IT: Linux, ZFS and Open-Source Licenses

 Computing, Politics  No Responses »
Aug 252007
 

If you’re hoping to read about Linux finally getting ZFS (except as a FUSE module) then you are going to be disappointed … this is merely a rant about the foolishness shown by the open-source world. It seems that the reason we won’t see ZFS in the Linux kernel is not because of technical issues but because of licensing issues … the two open-source licenses (GPL and CDDL) are allegedly incompatible!

Now some may wonder why ZFS is so great given that most of the features are available in other storage/filesystem solutions. Well as an old Unix systems administrator, I have seen many different storage and filesystem solutions over time … Veritas, Solaris Volume Manager, the AIX logical volume manager, Linux software RAID, Linux LVM, …, and none come as close to perfection as ZFS. In particular ZFS is insanely simple to manage, and those who have never managed a server with hundreds of disks may not appreciate just how desireable this simplicity is.

Lets take a relatively common example from Linux; we have two disks and no RAID controller so it makes sense to use Linux software RAID to create a virtual disk that is a mirror of the two physical disks. Not a difficult task. Now we want to split that disk up into seperate virtual disks to put filesystems on; we don’t know how large the different filesystems will become so we need to have some facility to grow and shrink those virtual disks. So we use LVM and make that software RAID virtual disk into an LVM “physical volume”, add the “physical volume” to a volume group, and finally create “logical volumes” for each filesystem we want. Then of course we need to put a filesystem on each “logical volume”. None of these steps are particularly difficult, but there are 5 seperate steps, and the separate software components are isolated from each other … which imposes some limitations.

Now imagine doing the same thing with ZFS … we create a storage pool consisting of two mirrored physical disks with a single command. This storage pool is automatically mounted as a filesystem ready for immediate use. If we need separate filesystems, we can create each with a single command. Now we come to the advantages … filesystem ‘snapshots’ are almost instantaneous and do not consume additional disk space until changes are made to the original filesystem at which point the increase in size is directly proportional to the changes made. Each ZFS filesystem shares the storage pool with the size being totally dynamic (by default) so that you do not have a set size reserved for each filesystem … essentially the free space on every single filesystem is available to all filesystems.

So what is the reason for not having ZFS under Linux ? It is open-source so it is technically possible to add to the Linux kernel. It has already been added to the FreeBSD kernel (in “-CURRENT”) and will shortly be added to the released version of OSX. Allegedly because the license is incompatible. The ZFS code from Sun is licensed under the CDDL license and the Linux kernel is licensed under the GPL license. I’m not sure how they are incompatible because frankly I have better things to do with my time than read license small-print and try to determine the effects.

But Linux (reluctantly admittedly) allows binary kernel modules to be loaded into the kernel and the license on those certainly isn’t the GPL! So why is not possible to allow GPLed code and CDDLed code to co-exist peacefully ? After all it seems that if ZFS were compiled as a kernel module and released as a binary blob, it could then be used … which is insane!

The suspicion I have is that there is a certain amount of “not invented here” going on.

Computer Security

 Computing  No Responses »
Aug 102007
 

The UK news this morning (and last night) had an item on about plans to tackle the problem of phishing with various suggestions (most of which make sense). Similar stories about phishing and how people are being ripped off by fraudsters regularly come up on the news. One thing that rarely gets a mention except in passing with a suggestion to run a ‘protected computer’ is how regular computer users who ignore security are contributing to the problem.

Almost all spammers (and phishers) these days use botnets to spew out their sewage; as someone who runs a mail server for a large organisation I regularly take a look at where spams entered the Internet mail system. In the vast majority of cases it has entered via a location that is obviously a client machine operated by an ‘innocent’ person ignorant of what their computer is being used for.

There are plenty of places to point the finger of blame …

  • The companies who produce operating systems that are so vulnerable to being compromised when connected to the Internet.
  • Those who use viruses and worms to create ‘botnets’ of vulnerable machines to be used for a variety of purposes.
  • The ISPs who irresponsibly fail to block outgoing mail not going through their mail servers. Whilst some (me!) should be able to opt out of such a block because we (I) run our own mailserver it should not be open by default.

Finally, the person who runs a computer irresponsibly is also to blame. Obviously not everyone wants to become a security expert, but there are a few easy steps to make it more difficult for your computer to be broken into. And they should accept that if they get infected they could get slung into a ‘quarantine’ … ISPs can and should be able to detect infected machines being used by spammers and sling them into a ‘quarantine’ network with limited functionality. This ‘quarantine’ is dead simple to setup, as I’ve done it myself.

To reduce it to an analogy, if you were to leave a car parked with the handbrake left off are you totally blameless if someone leans against the car and it rolls down a hill and kills someone ? People tend to regard leaving an infected computer online as being a trivial matter; it is not.

Bill Gates, OLPC Project, Educational Content

 Computing, Politics  No Responses »
Jul 292007
 

Just seen part of an interview with Bill Gates on News24 where Microsoft’s educational projects were being discussed, and the One Laptop Per Child project was brought up. Bill sort of avoided trying to talk about it by claiming that hardware costs will continue to come down and the real problem is about educational content.

It is true that hardware costs tend to come down … to a point where prices stay fairly static but specifications increase. He has also glossed over the fact that the OLPC laptop is semi-ruggedised with features specifically intended to help with its use as a learning tool rather than a working tool; including the special display which has a special low-power black and white mode intended for reading eBooks. Not something found in a typical laptop!

The other thing that was totally ignored is that the Sugar user interface (running on a stripped down RedHat) is designed to be easy to use for children rather than rely on some conventional approach to desktop computing. For instance there is an easy way to see your local “neighbourhood” (press F1) … the local mesh of internetworked OLPCs.

However Bill hit the nail on the head by bringing up the content issue. It is the real problem and in fact the OLPC project highlights this and has a prominent area on their Wiki to deal with content. Perhaps Bill should put his money where his mouth is and help fund the content projects … it may not help Microsoft directly (although given that the content is intended to be “open-source” there is no reason why a Microsoft operating system could not use it as well as the OLPC laptops) but it would help education.

IT: Nokia E90 – The First Few Hours

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Jul 282007
 

I have been a PDA user for many years (since the Psion 3 although I’m no Psion groupie … I’ve been through Palm devices and the Sharp Zaurus on the way to the E90), and have carried a separate phone. This of course has disadvantages in that the PDA is not generally “connected” and it is all too often left behind when you don’t think it will be needed … for instance on the little 70 minute stroll I’ve just taken. I’ve always been intrigued by the Nokia Communicators not least because they had more or less evolved from the old Psion 5 (which had the best damn keyboard that a PDA has ever had and probably will ever have), but had always steered clear because I had always stuck with the phone provided by my mobile provider.

I eventually (early 2007) went SIM-free mostly because the free phones provided with a phone contract were getting nastier and nastier, and got myself a Nokia N80i. Then I heard about the E90 and kept thinking about ‘converging’ my PDA and phone, and when it became available hit the button to get one. It turned up yesterday afternoon (after a whole day of waiting in for it 🙁 ).

Opening The Box

After clearing away a few freebies provided by the phone seller … including a pointless piece of ribbon for dangling the phone around someone’s neck (not mine! Being a little more paranoid than most I don’t like providing an attacker with a ready made garrotte), and a mysterious 10cm circle of sticky silicon, I find the phone. Big and red.

Take a 3cm thick A5 pad and chop into three equal sized pads and you get something more or less the same size. Small enough that it will still fit in my front jeans pocket, but big enough that it is now difficult to take notes out … time to rethink how I organise my pockets or possibly get one of those quaint belt cases. Picking it up and you instantly realise that you are holding something that is not cheap and nasty.

The battery compartment cover is a bit fiddly, but not so much so that if you swap batteries regularly you will dread that time coming. The slot for the SIM is great … just slide it in rather than have some kind of nasty bracket in there to make things fiddly. Put the battery in and you’re ready to go … nice that the battery is provided with some juice in it unlike some high tech gadgets where you are supposed to charge the battery overnight before turning the device on.

Getting the 1Gb mSD card inserted is no more fiddly than any fiddling with mSD cards is. Who decided mSD was a good idea anyway ? SD cards themselves are small enough themselves, mSD is too small; accidentally drop it onto a shag-pile carpet and you’ll spend half an hour hunting for it. Not that I have such a carpet of course!

And no Nokia pop-tart connector! Instead you get a mini-USB connector and a 2.5mm headphone/microphone connector. That is a relief … the engineer who came up with the pop-port was obviously coming off a 10-day bender … ok concept, awful execution.

First Poweron

I plunged straight in … just opened the clamshell and started using the big screen and keyboard. Kind of a surprise seeing the old Nokia startup graphics on an 800-pixel wide screen. The screen itself is bright and sharp, and probably perfectly readable outside. The default font is kind of large on such a screen (but is tweakable so you can see more on screen). The keyboard is pretty good as well. Although not a particularly full travel each key does give positive feedback, better than the Zaurus! However it is kind of small and it is all too hard to miss the key you are aiming for and hit another by mistake (although I have noticed my accuracy towards the end of this ‘first few hours’ has improved). Odd because by reducing the over-sized ‘special’ keys at both sides of the qwerty pad it should be possible to make the main keys ever so slightly bigger.

Straight from the beginning, the E90 was perfectly functional as a phone; a quick delve into the “Data Mover” and my contacts from the N80i (and gallery contents, notes, etc) were flashed across bluetooth onto the E90. A quick bit of configuration and the phone is online using my WifI router. Following my own instructions and my calendar was synced to the corporate calendar. At this point I was effectively finished at setting things up with the exception of figuring out some way of getting my iqnotes data onto this phone (some hacking with Perl to import them into ActiveNotes).

Candybar Mode

Shut, the phone actually works better for receiving or making calls than an ordinary mobile; the size is more comfortable and unlike the N80i it doesn’t try to rip out my beard. The keys on the top are larger than modern phones and easier to use; with the exception of the “green” and “red” buttons which share space with a total of six buttons and the navikey. It makes it difficult to hit the right key and there is plenty of space for an additional row of keys. Kind of irritating as I can see myself using the “smartphone” functions in closed mode very rarely and the additional keys are only necessary when using the “smartphone” functions.

However the screen whilst relatively small for a smartphone (it is after all, effectively just a secondary screen) is pretty good and perfectly visible outside (I did test the small screen outside) although I have not had the opportunity to test it in bright sunlight (currently rather rare in the UK). It is even readable enough in powersave mode to read the time (something I sometimes found tricky on the N80).

VoIP (Truphone)

Following the instructions to ‘re-install’ Truphone (my VoIP provider of choice seeing as it is a UK company, and currently gives me free calls to UK landlines in addition to many other destinations) and it was on the phone and ready for testing. A quick phone call showed everything was working fine. The provided headset seems to be even better than the one provided with the N80i and would probably work perfectly well for listening to music.

Truphone itself is almost invisible disappearing seamlessly into the native interface, just allowing the “Internet” option to the “Call” menu to function via Truphone. I only use Truphone at home, but I see there are multiple profiles to allow Truphone to work in multiple locations with different Internet connections.

Web Browsing

I am not normally one for browsing the web on a small screen, but the Nokia web browser on the E90’s screen works well enough that I used it to visit my Del.icio.us bookmarks for the Nokia smartphones (mislabelled Nokia_N80) to download additional tools (well I also used the native “Download!” thing as well). Incidentally if you haven’t already tried it, using Del.icio.us for your bookmarks is quite useful when you have more than one computer to use them from … assuming you don’t mind your bookmarks being public of course!

The browser will “zoom out” to display an overview of the entire web page if you keep travelling around the page too long. Possibly more useful on a smaller screen than the E90’s where it does seem to get in the way. Another oddity is that the “Back” button we find in all browsers does not just go back to the previous page, but gives you a scrollable list of overviews so you can travel back more than one page easily. Perhaps it is just something one needs to get used to, but I frequently found myself going back further than I intended.

Summary

This one is definitely a keeper, and I’ll probably be keeping it for quite a long time. It does pretty much everything I need although a serial port would be nice for those odd occasions when I need something portable to connect to the console of a Sun E6900 (there is something oddly perverted about using a handheld computer for controlling an enterprise computer with more CPU cores than is easy to count and is the size of a full rack). Many of the “rough edges” I have noticed so far, are things I will get used to like the size of the keyboard, etc.

The only disappointment has been the GPS device which won’t work although that is probably because mostly I’ve been trying it indoors … not wise!

Now I’m off to throw that mysterious silicon circle against the wall for amusement … it sticks!

Why Rockbox Your iPod, iRiver, Gigabeat, or Archos Audio Player

 Computing  No Responses »
Jun 212007
 

I have been stimulated into writing this by a slashdot article (not worth linking to) where people were arguing about the merits of installing Rockbox onto a compatible audio player … such as the iPod. Some people seem to think that replacing the standard iPod software is heresy!!

Or at the very least are complaining that Rockbox does not work the same way as the standard firmware.

I am in a somewhat odd situation … I bought an iPod after I was aware that Rockbox supported the iPod (and specifically avoided the 80Gb Ipod as it wasn’t supported at the time) to replace a rockboxed iRiver iHP100 (more commonly known as an iHP110) that was suffering from a lack of battery “oomph” (and yes I had tried replacing the battery). I spent probably just a couple of minutes in the native firmware before switching to the Rockbox firmware because I did not want to re-encode several thousand OGG-encoded tracks.

Now obviously I cannot criticise Apple’s interface or functionality on the iPod because I have not really used it.

However I can say that the Rockbox firmware is a perfectly adequate interface to run on an iPod and is getting better every week. Some of the features the Rockbox has include :-

  • Multi-codec support to play MP3, OGG, FLAC, AAC, WAV, … encoded files. I haven’t pulled down the full list but you really cannot get an audio player offering more codec support on a portable device. Not everyone needs this of course, but it is nice to have the choice.
  • The default Rockbox interface is kind of ropy on the iPod, but it is “themable” and some of the themes are pretty good … just have a look at the Rockbox Themes website (I have linked to the iPod Video themes)
  • Numerous “plugins” for playing games, displaying photos and other miscellaneous things. I must admit I don’t use them too much, but being able to play Jewel whilst bored waiting somewhere does come in useful.
  • The standard mass storage method of storing audio tracks in a way that can be easily accessed outside of iTunes does mean it is easier to copy some tracks to another computer easily. Of course I mean the freely distributable tracks!

Rockbox does have some disadvantages … the battery life is relatively poor compared with the native firmware (but very much better than an iHP100 with a tired battery!), and if you have a lot of investment in iTunes you will suffer from the lack of support (although the Rockbox database will track down files stored on the iPod whether they were put there by iTunes or just copied).

The most sensible advice for an iPod user thinking about making the switch is just to try it out. You may like it or you may not, but you don’t have anything to lose as you can always go back to the standard firmware. In fact as you can easily switch from one to the other, you can try out Rockbox gradually over time … go back to the native firmware when you are lost, and go back when you are feeling adventurous.

Another advantage that the existent Rockbox provides, that many people miss is that it may just put some pressure on Apple to improve their native firmware. If Apple notices that many of their iPod customers install Rockbox, they may be inclined to take a look themselves and start implementing features in their native firmware to “keep” their customers … surely something that would be good for all iPod owners.

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