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Another IPv6 instalment (subtitled: Watch Your Tech Library Currency!)

Mar 26

Posted by Vic in Gadgets, Hardware, Networks | No Comments

I made a somewhat cryptic tweet a little while ago about how I spent a crazy-long period of time researching what was, I believed, the next-big-thing in DNS resolution for IPv6 (or so my 2002 edition of “IPv6 Essentials” told me).  I could not work out why I saw nothing about A6 records in any of the excellent Hurricane Electric IPv6 material or in any other documentation I came across.

The answer should have been obvious: DNS A6 records (and the corresponding DNAME records) never caught on.  RFC 3363 recommended that the RFC that defined A6 and DNAME (RFC 2874) be moved back into Experimental status.  If I hadn’t been using an old edition of the IPv6 book, I might never have even known the existence of A6 and not have wasted any time.

In my previous post on IPv6 I theorised that we are in the early-adoption phase of IPv6 where things aren’t quite baked, and yet now I’ve picked up a 9 year old text on the topic and acted all surprised when it got something wrong.  It was a bit stupid of me; had I bought a book about IPv4 in 1976, might it have been similarly out of date in 1985?

As always though I’m richer for the experience!  Or so I thought…  Like many, I’m becoming increasingly time-poor.  When I bought a book on IPv6 some years ago I thought I was making an investment, but it turned out that my investment actually lost for me in several ways:

  1. The book took up physical space in my bookshelf for all that time I wasn’t using it
  2. I didn’t actually use the information at the time I acquired it
  3. The time I could have got value from it was wasted by it idly sitting on the shelf
  4. Once I did try to use it, it actually cost me time rather than saved time

I came to think about the other books on my shelf.  It’s pretty easy to recognise that a book that proclaims to be up-to-date because it “Now covers Red Hat 5.2!” will be anything but.  Also, from the preface of a Perl programming book that says “this was written about Perl 5.8, but it should apply to 5.10 as well” I’ll be forewarned that things will be fairly applicable to 5.12 but maybe not to Perl 6 when it’s out.

Technology usually has a somewhat abbreviated lifespan, so therefore the corresponding documentation will have a lifespan correspondingly short…  Here, however, is an example of a technology that will have a far greater lifespan (we hope) than much of the documentation that currently exists around it.  I emphasise “currently exists”, because it won’t always be that way: IPv4 was pretty well-baked by the time I had anything to do with it, so I could have bought a book on IPv4 with next to no concern that it was going to lead me astray (indeed, I bought W. Rich Stevens’ TCP/IP programming texts during the 1990s, and still use them to this day).  I keep forgetting that I’m on a completely different point of the IPv6 adoption curve, and the “experts” are learning along with me.

So, a new tech library plan then:

  • Reduce dependence on physical books (okay, this one is already a work-in-progress for me) — they don’t come with you on your travels as easily, and (more important in this context) they’re harder to keep up to date.
  • Before regarding the book on the shelf as authoritative, check its publication date.  If it’s more than three years old, depending on the subject matter it might be out of date.  Check if there’s a new edition available, and consider updating.  If there’s no new edition, check for recent reviews (Amazon, etc).  Someone who just bought it last month might have posted an opinion on its currency.
  • If you have to buy a paper book, don’t buy a book on any technology that is a moving target.  On the same shelf as my copy of “IPv6 Essentials” there is a book entitled “Practical VoIP Using VOCAL”.  I never even installed VOCAL, and I’m sure many current VoIP practitioners never heard of it.  (Side note: I think it’s strange that I bought that book, and a Cisco one, but still to this day have never owned a book on Asterisk.  Maybe I have some kind of inability to pick the right nascent-technology book to buy.)
  • Use bookmarking technology more! I have a Delicious account, and I went through a phase of bookmarking everything there.  I realise now that, if I was a bit more disciplined, I could actually use it (or a system like it, depending on what Yahoo! does to it) as my own personal index to the biggest tech library in existence: the Internet.

That first point is harder than it sounds (especially for someone like me who has a couple of books on his shelf with his name on the cover).  My Rich Stevens books are littered with sticky-note bookmarks for when I flick to-and-fro between different programming examples.  Electronic readers are still not there when it comes to the “handy-hints-I-keep-on-my-lap-while-coding” aspect of book ownership.

I have a Sony Reader which I purchased with the intent of making it my mobile tech library.  It’s just not that great for tech documents though, since it doesn’t render diagrams and illustrations well (it also isn’t ideal for PDFs, especially in A4 ratio).  This may change as publishers of tech docs start releasing more titles on e-reader formats like ePub.  The iPad is working much better for tech library tasks; I’m using an app called GoodReader which renders PDFs (especially RedBooks!) quite well and has good browsing and syncing capability as well.

More on these topics later, I’m sure!

Update: I omitted another option in my “tech library plan” — since IPv6 Essentials is an O’Reilly book, I could have registered with their site to get offers on updating to new editions.  Had I done so, the events of this post might not have happened!  Now that I’ve registered my books with O’Reilly, I’m getting offers of 40% off new paper editions and 50% off e-book editions.  Also, in line with my reduce-paper-book-dependence policy, I can “upgrade” any of the titles I own in paper to e-book for US$4.99.  If you haven’t already, I encourage anyone who has O’Reilly books that they rely on as part of their tech library to register them at members.oreilly.com.  (This is an unsolicited endorsement from a happy customer, nothing more!)

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Sharing an OSA port in Layer 2 mode

Nov 4

Posted by Vic in Hardware, Linux, Networks, Work | No Comments

I posted on my developerWorks blog about an experience I had sharing an OSA port in Layer 2 mode.  Thrilling stuff.  What’s more thrilling is the context of where I had my OSA-port-sharing experience: my large-scale Linux on System z cloning experiment.  One of these days I’ll get around to writing that up.

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Asterisk and a Patton SmartNode

Jul 26

Posted by Vic in Hardware, Linux, Telephony | No Comments

It’s been ages since I did an update on the main network machine here, and I bit the bullet over the weekend. 250+ packages emerged with surprisingly little trouble, and all I was left to do was build the updated kernel and reboot.
I usually end up with something that doesn’t restart after the reboot, usually because of a kernel module that needs to be rebuilt after the kernel (because I forget to remerge the package before the reboot, oops). This time the culprit was Asterisk (the phone system), which I also often have trouble with after an update due to a couple of codec modules external to the Asterisk build. This time however the problem ended up being due to the Asterisk CAPI channel driver failing.
Thinking it was the usual didn’t-rebuild-the-module problem, I went looking for the package I had to rebuild… only to find it was masked. Turns out the driver for the ISDN card in the box, a FritzCard PCI, is no longer maintained and doesn’t build on modern kernels, which has resulted in the Gentoo folks hard-masking the entire set of AVM’s out-of-tree drivers.
Help was at hand in the form of a Patton SmartNode 4552 ISDN VoIP router I’d bought months ago to replace the Fritz card. Even though there isn’t much information about how to configure the SmartNode for Asterisk around, I managed to get the setup working in only a couple of hours. I even managed to get the outgoing routing for the work line set up right!
Eventually I’ll get something posted here that goes into a bit more detail about the configuration. Let me know in a comment if you need to hurry me up! :-)

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ppc Linux on the PowerMac G5

Apr 18

Posted by Vic in Hardware, Linux, Operating Systems | 3 Comments

With Apple’s abandonment of PPC as of Snow Leopard, I began wondering what to do with the old PowerMac. It’s annoying that so (comparatively) recent a piece of equipment should be given up by its manufacturer, but that’s a rant for another day. Yes, we can still run Leopard until it goes out of support, but with S and I both on MacBook Pros with current OS I know that we would both become frustrated with a widening functionality gap between the systems.

I had always resisted runing Linux on the PowerMac, thinking that the last thing I needed was yet another Linux box in the house. I had tried a couple of times, but it was in the early days of support for the liquid cooling system in the dual-2.5Ghz model and those attempts failed dismally. I figured that by now those issues would be resolved and I would have a much better time.

I assumed that Yellow Dog was still the ‘benchmark’ PPC Linux distro, so I went to their site. I saw a lot of data there about PS3 and Cell; it seems that YDL is transitioning to the cluster and/or research market by focussing on Cell.

The next thing I discovered is the lack of distributions that have a PPC version, even as a secondary platform. My old standby Gentoo still supports PPC, as does Fedora (I think: I saw a reference to downloading a PPC install disk, bit didn’t follow it), but every other major distro has dropped it — openSUSE, for example, with their very latest release (their download page still has a picture of a disc labelled “ppc”, but no such download exists, oops). I guess that since the major producer of desktop PPC systems stopped doing so, the distros saw their potential install base disappear. Unfortunately for those distros, I can see the reverse happening: now that Apple has fully left PPC behind, plenty of folks like me who have moderately recent G4 and G5 hardware and who still want to run a current OS will come to Linux looking for an alternative… I guess time will tell who is right on this one.

So I went to install Gentoo, and to cut a long story short I had exactly the same problem as before: critical temperature condition leading to emergency system power-off. I found that if I capped the CPU speed to 2Ghz I could stay up long enough to get things built, but then the system refused to boot because it couldn’t find the root filesystem. Probably something to do with yaboot, SATA drives and OpenFirmware. So again I’m putting it aside.

My next plan was to treat it as a file server. Surely a BSD would support my G5 hardware: after all, Mac OS X is BSD at heart… Well, no. FreeBSD has no support for SATA on ppc, OpenBSD specifically mentioned liquid-cooled G5s as having no support, and I don’t think I saw any ppc support on NetBSD more recent than G3 [1].

This is one of the things that annoys me about the computer industry: that somehow it’s okay to so completely disregard your older releases. What if the automotive industry worked that way?

So I may yet try Fedora, or give the game away for another year or so and see what the situation looks like then.

[1] I may have mixed up a couple of these details.

Edit: Gentoo’s yaboot has managed to make it so that I can’t boot Mac OS X on the machine any more.  Oh dear.

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Upgrading from Cisco

Aug 21

Posted by Vic in Hardware, Telephony | 1 Comment

In case you weren’t aware, I am a VoIP nutcase.  I have an Asterisk phone system at home, and all the phones in the house are VoIP of some description (either real VoIP devices or analogue handsets through an ATA).  While I haven’t converted to VoIP as a replacement for PSTN, I have some connectivity to VoIP providers both here and overseas (and soon to be more, to help the phone-home situation while I’m overseas).

I’ve been a user of Cisco IP phones, buying 7960s and a couple of 7970s through a well-known internet site (maybe it starts with an “e”, not sure).  The phones have been excellent, and I’ve even written a few XML apps to supplement their use here.  The 7960s are getting a bit dated now, however, and I found myself contemplating buying 7971s (or even something newer, like the 7965 or 7975).  Before I committed myself further into the relationship with Cisco, though, I thought about what I was really getting out of using Cisco phones.

Like many users of second-hand Cisco gear, I only purchased the hardware.  I do occasionally succumb to a nagging feeling of being an “outlaw” (at least in the eyes of Cisco), but admittedly that feeling usually only comes when I find out that Cisco has released another new version of SIP software that I can’t get because I haven’t paid for SmartNet.  The last time I had this thought though, I had a realisation: even if I did pay for SmartNet, the only thing I’d get would be the firmware: Cisco will only support their phone software when connected to their CallManager server (yes, even the SIP firmware).  Anyone running Cisco phones against anything other than CUCM gets no support from Cisco in the event something doesn’t work–and based on the information floating around, the problems are many.

So basically I would be paying Cisco to allow me to run one of the worst SIP implementations in embedded existence, with no opportunity to report problems with it in my environment.  Hmm, let me think about that for a minute…

At around the same time, I happened across the NerdVittles site, and in particular the post where NerdUno nominated the Aastra 57i as the “World’s Best Asterisk Phone“.  I started to do some research into it, and was astounded at the level of support the manufacturer (a Canadian company which a few years ago acquired the telephony business of a little mob called Nortel) and the community provide for this phone and Asterisk.  Looking through the phone manual, I found functions that only work with Asterisk! I found a full set of integration scripts that provide XML applications, right through to automatic provisioning tools.  Possibly the best thing was that on the product page for their phones — right there on the page that descibes the product — are links to current versions of firmware, documentation, XML application development guides, even a Linux-based application to encrypt the phone configuration files.  Not hidden in some obscure hard-to-find portal, or behind a registration-only support site.

I started to think of the possibilities…  I’d be able to freely modify the phone configuration (even via a HTTP interface if I so chose), without having to make trial-and-error changes to a cryptic and totally undocumented configuration file.  I’d be able to write XML apps without having to do laborious debugging to cater for why the parser was choking on XML that was perfectly okay according to the documentation but apparently tripped over an undocumented field length restriction or character encoding limitation.  I could get access to things like Visual Voicemail, BLF, integration with Asterisk functions like day/night mode and call parking.  I could keep the phones up-to-date for new functions and bug fixes.  With a click of a mouse I could get proper Australian tones!

So, I decided to give one a try.  Finding nothing on that “e” site I went looking for a vendor locally, and found several places that would sell one to me (legitimate e-tailers, no less!  Zounds!  A VoIP phone with a warranty?  You jest!).  It took a while for my chosen vendor to source it for me, but I’ve had it now for a couple of weeks.  It’s probably going to take a while for it to live up to it’s full potential in my installation, but since that potential is so much greater than what I have been able to do with the Ciscos I think I’m already ahead.

More in the coming weeks as the Aastra settles in.

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Classic Mac sounds on my mobile phone

Apr 9

Posted by Vic in Fun, Hardware | 1 Comment

We watched WALL-E the other day. A bit of trivia for Apple Mac fans (if you didn’t already know) is that WALL-E’s startup sound — heard when he’s finished his solar recharge — is that of a post-1997 Mac computer (with Steve Jobs on the board of Pixar and Disney, WALL-E was never going to make The Microsoft Sound (: ). Coincidentally, at around the same time as I saw WALL-E I was going through that modern malaise of mobile-phone-alert-tone-taedium… So, inspired by this bit of cinematic crossover coolness, I decided to get some Mac-chime action for my handset.

The first thing was obviously to get hold of the audio file. This turned out to be surprisingly easy, thanks to Google pointing me to a piece of software called MacTracker. MacTracker is actually a reference guide for Apple products (computers all the way back to the Macintosh XL, the MessagePads, printers, displays, even iPods and mice), but part of the information it holds about the computers is their startup and death chimes.

There’s no option in MacTracker to export the audio files, but by opening the app package (“Show Package Contents” in Finder) it’s possible to navigate to where the chime sound files are stored. Then from Finder, all I had to do was zap the file to the phone via Bluetooth. On the phone, opening the Bluetooth message gave me an option to save the “music” file, which I did — this adds the file to the Music Player, but importantly makes it easily selectable in the configuration of the alert tones.

So now when I receive an SMS I hear the death chime of a Macintosh LC, and the startup sound of the Twentieth Anniversary Macintosh alerts me to incoming e-mail. I’m going to apply similar configuration to my desktops: on-and-off for the last ten years I’ve been using a Homer Simpson soundbite to advise incoming mail, and it’s a bit tired now…

Next task will be to replace the startup sound on my N810 with something a bit retro-Mac! :)

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Living with an iPod touch

Dec 11

Posted by Vic in Hardware | No Comments

I held out for a long, long time. I'd even talked myself entirely out of getting one. Like they say in the classics though, "you think you've escaped, but they pull you back in". I now have a 32GB iPod touch and it's doin' alright, even though it took me nearly a week before I bothered putting any media on it!

I think what finally did it for me was the App Store. I love being able to simply go to an app on the device and easily look for software, installing what I like with no fuss. I especially like the fact that my downloads are synced with my computer, so that I don't have to keep track of all the individual items I've installed (unlike my phone; I can't think where all the sis and sisx files for different stuff I've installed might be).

My Facebook friends will know that I'm much more active there suddenly. Why? The Facebook app on the Touch — I no longer have to start up a computer or open a browser to update my status or reply to comments. I had a bit of this function with Fring's Facebook interface on my phone, but the large screen of the Touch makes things like this much more friendly.

I came very close to getting an iPhone actually — but not to use as a phone. This was after I'd realised that it's just as valuable as an Internet-connected device as an actual phone. The cost of iPhone service is still a bit prohibitive to me though, especially for an occasional-use device.

One of the things that had turned me off was the closed nature of the iTunes ecosystem (iPod, iPhone, Apple TV, iTunes). People sometimes ask me about Skype, and I say that the worst thing about it is that it Just Works. I mean, it's a closed system with no interconnections other than those provided by Skype themselves — by this nature it should fail, and yet because it works (arguably) better than any other desktop VoIP product it enjoys immense success. Same goes for Apple's stuff: the iTunes ecosystem Works And Works Bloody Well.

I've been thinking for ages about sync for calendar and contacts and stuff; I've been hunting for services and software and tools for ages. I could build something myself, and indeed started to (I've looked at Google Apps, used Chandler, checked out Ovi, and played with Sync4J before it was called Funambol). I could spend time and effort coming up with something myself…

Or I could just buy an iPod.

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New gadget: Nokia E71

Aug 23

Posted by Vic in Hardware | No Comments

I have been in the mobile phone market on-and-off for nearly 12 months. There wasn’t really anything wrong with the N70, I guess I was just getting a little fidgety with lots of new “shiny” going around. The trip to the US in May, and seeing an iPhone in person for the first time, probably didn’t help, nor (obviously) did the local release of iPhone 3G. Once I’d talked myself out of getting an iPhone though, the itch was still there… and I must say it’s being well-and-truly scratched by the E71.

I’ve had this phone for just on a week now, and it’s certainly one of the best phone purchases I’ve ever made. In a nutshell, the key things about it are:

* QWERTY keyboard, in a form factor not much larger than the N70. Importantly, it’s much smaller than the E61 that preceded it (now there’s a phone that was just MADE of ugly). Despite it’s size the keyboard is amazingly easy to type on, although I may have to update this after I give my thumbnails a trim.

* Symbian OS. Maybe I’m biased, as the owner of a Psion 5, but to me Symbian has an edge over other phone OSes. Not only with the functions in the handset and Nokia’s Series 60 interface, but the range of third-party apps for Symbian (or Series 60 specifically) is great. Almost straight after charging the battery I downloaded PuTTY (SSH client) and “vejotp” (S/Key one-time-password utility). Plus, the recent news that Nokia intends to open-source Symbian is a great thing.

* Nokia Maps and A-GPS. While the iPhone glitterati download the entire UBD or Melways every time they walk down the street thanks to Google Maps, I get quick GPS mapping for zero download (the last few times I’ve used it, the download counter has stayed stuck on “0.0kb” even though A-GPS is supposed to cost a bit of data every startup). It’s not the most accurate GPS ever made, for sure, but it’ll do me for now at least.

* Built-in podcast support. I was getting more and more frustrated with the way that Amarok and iPod fought with each other over my podcasts. It never seemed to work as well as it did on iTunes! Now, I can use the device I download the podcasts with to listen to them as well. It’s self-contained, tidy (no more podcasts mixed in with the music library and causing havoc), elegant.

* Wi-fi capability and SIP client. Being able to connect to the home network obviously means that I can do things like update my podcasts without having to second-mortgage the house to pay for HSDPA data. The SIP client is very cool too: I’ve connected it to my Asterisk box, and now have a cordless home phone and mobile in one device.

* Solid construction. It’s got to be the most sturdy-feeling phone I’ve ever owned. The case is metal, and it has a nice weight to it. The buttons feel solid, almost like real keyboard keys.

* Drop-dead gorgeous. I got the grey version, the metal casing looks like titanium and has a glossy finish (which is a little prone to fingerprints, but cleans easily). The screen is just amazing, usable in daylight, bright and colourful and incredibly high resolution.

I’ll mention more as time goes on, but for now I am very happy!

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Motion Computing Tablet PC

Aug 13

Posted by Vic in Hardware, Work | No Comments

Thanks to work, I am now the possessor of a rather cool piece of kit: a tablet PC. It’s a Mobile Computing LE1700, and I’m quite impressed with how it works. The big question though is of course… Will it run Linux?

At the moment it’s still running Windows XP Tablet Edition, but that’s only because a Hardy Heron install DVD is quite some way away from me right now.

I just trained Microsoft speech recognition and this paragraph has been dictated using speech recognition.  The recognition rate is actually quite good for the amount of training I’ve done, although I am having to go back and correct quite a few minor errors.

Back to handwriting recognition, which is outstanding: it’s only just now, as I write on the screen of this device, that I realise how poor my handwriting has become! Almost certainly this is due to lack of practice and under-use! I can tell as I’m writing that its recognition is somewhat dictionary-based, as if I pause or lift the pen it will make a guess abort what I’ve written which it will change as I complete the word.

Credit where credit is due, I think tablet Windows looks pretty good. Having used it before just putting Ubuntu on, I’ll be expecting a bit more from Linux…

On the hardware side, the machine looks quite sturdy and solid — so much so it’s a bit or the weighty side. I did install the additional battery pack though, and I’m sure that if I was adopting a proper tablet-PC posture it wouldn’t feel as heavy as it does. It has a 3G modem built-in, which works fine with my Telstra USIM (that’s how I’m posting this now), and the usual complement of Wi-Fi, Bluetooth, PC-Card, SD  and infra-red. It even has a place to stow the pen-stylus.

As I said, I don’t have a Linux disc handy to start setting up properly so the big Linux question will have to wait for a while. Some early Googling shows that there is support for most of the hardware components in it (the digitiser is Wacom, the Wi-Fi is Intel 3945, I’ve even seen support for the 3G adapter. It’s the interface and application level that I’m worried about — the state of handwriting recognition, whether XRandR lives up to the promise, and so on. I’ll post more as I get used to it and see what it can do…

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Laptop hard disk replacement, part two

Jun 23

Posted by Vic in Hardware | No Comments

Way back in May I had a hard disk in my laptop fail, and after the warranty replacement disk showed up it took me a few days to get around to doing the replace. It didn’t get off to a very good start though…

In the past when I’ve done this kind of recovery I copied the details of the partition table and copied each partition in turn off the failed drive. This time however in my haste (or something) I imaged the entire 80GB in a single file by using dd pointing at the disk device node (/dev/sda, say) instead of each partition.

When it came to restore, this brought me undone. I tried the reverse of what I’d done to create the image, just dd to the disk device node, but at around the point where the first partition would have ended it failed with an I/O error.

Assuming that I did actually have a valid image of the entire drive, I needed to find a utility that would treat a disk file as an image of an entire drive, partition table and all. Then, theoretically, I could copy each partition out of the source file in the same way I was used to.

As usual, the lazyweb came through for me. I found a beaut utility called kpartx, apparently part of multipath-tools. I also found some blog posts describing how to use the tool for what I needed. What kpartx does by itself is scan a block device or normal file (significant, as I’m sure when I first used it I had to use losetup) and create device-mapper mappings to the partitions it finds. kpartx was just what I needed!

This blog post describes the process I went through (and no losetup here either). For me, I let kpartx create device-mapper nodes for the partitions in the disk image, and then used dd to copy from each of those partitions to the real partitions in the new disk (carefully created using fdisk to match the originals). Then I set up grub on the new disk, and installed it into the laptop. It worked first go!

So now on its third hard drive, this Sony Vaio (same one with the weird wireless issue in Hardy) gets yet another lease on life. The battery is almost expired though, so I think it won’t be long before it goes to the Old Hardware Shelf…

Edit: I realised my confusion about losetup. kpartx uses losetup under the covers if it detects that you’re trying to work on a disk file instead of a block device. When you use the -a or -l switches to kpartx, if it needs to it straps up a loop device for you and automatically works on that; running kpartx with the -d removes not only the device-mapper nodes but the loopback node as well.