Tutorial: wheezy live iso-hybrid with persistence on USB

As of wheezy, Debian no longer offers for download any prebuilt hdd (formerly known as usb-hdd) live images, which, in squeeze, were necessary if you wanted to use persistence. The good news is, since the new wheezy iso-hybrid images use xorisso, you can copy an image to a USB key and repartition it to add a persistence partition. Unfortunately, the filesystem itself is read-only, so you have to manually append the persistence boot parameter each time you boot the image. If that doesn’t bother you, you can skip this whole tutorial and just follow the instructions in live-manual for adding a persistence partition and you’re all set.

This tutorial explains how to extract the contents of a wheezy iso-hybrid live image to a USB key and modify it to boot with this parameter permanently enabled. I am writing it solely as a workaround and do not endorse this as a means to customize Debian Live images in general. I would love to help make a more convenient, supported way to accomplish the same thing for a future release. Meanwhile, the supported and recommended way to make any change to a Debian Live image is to build it from scratch using live-build, as described in live-manual. A simplified Debian Live Images Autobuilder web service is available that works well for many common customizations, if you prefer. Please use one of these methods if you want to do this, or other customizations in the supported way. Otherwise, read on.

Prerequisites

  • You need to download a Debian iso-hybrid live image. For this tutorial, I will use the Debian live wheezy amd64 LXDE image:
  • Note the size of the image. With ls -lh debian-live-7.0.0-amd64-lxde-desktop.iso you can see the image size for this example is 854M. Later, you will use this size plus 5% for the size of the partition to receive its contents.
  • You need a USB key large enough for both the image itself and your persistence partition. For this image, you could even use a 1G key, although that would leave very little space for persistence. In this tutorial, the test key is 8G, leaving lots of room on the key for growth.
  • I assume for this example you are preparing the key on a Debian or other Linux system that automounts media when they are plugged in, a fairly normal configuration.
  • This tutorial also uses the following tools, which you will need to install if you don’t have them already:
    • parted
    • mbr
    • dosfstools
    • p7zip
    • syslinux

Identify the USB key device

Caution: Always double-check the device you are writing to is the correct one to avoid losing precious data. There are two things to do to protect yourself. The first is, don’t write the USB key as root. The second is, first use ls -l /dev/disk/by-id to identify which device is the target USB key.

lrwxrwxrwx 1 root root  9 Jun 22 11:58 
usb-SanDisk_Cruzer_Contour_0000184CA87406BC-0:0 -> ../../sdb

As you can see, my SanDisk Cruzer Countour is /dev/sdb. For the rest of the tutorial, I’ll be referring to this device as /dev/sdX to avoid unfortunate cut-and-paste disasters. When you follow along, make sure you substitute the correct device for your USB key on your system.

Initialize the USB key

Start by plugging in the key and unmounting any automounted partitions to ensure nothing is accessing the device, e.g.

$ umount /dev/sdX1

Now make changes to the partition table. Use parted because it may be run as an ordinary user and has some advanced capabilities beyond more basic tools like fdisk.

$ /sbin/parted
WARNING: You are not superuser.  Watch out for permissions.
GNU Parted 2.3
Using /dev/sdX
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print devices
/dev/sdX (8221MB)
(parted) select                                                           
New device?  [/dev/sdX]?                                                  
Using /dev/sdX
(parted)

Note that when run as an ordinary user, if you only have one removable drive (which may include mp3 players, cameras, e-readers) plugged in, parted immediately selects that device. But just to be sure, use print devices to list the devices and select to if you need to select a different one, as shown above.

Repartition the USB key

Once you’ve verified you have the correct device, start repartitioning. Write a new partition table with mklabel msdos to wipe out all of the old partitions on it. You may skip this step and adapt the remaining instructions if there are partitions you need to keep. This is your last chance to bail if the device is wrong, so make sure it is the correct one before proceeding.

(parted) mklabel msdos
Warning: The existing disk label on /dev/sdX will be destroyed and all data
on this disk will be lost. Do you want to continue?
Yes/No? y
Error: Partition(s) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 on
/dev/sdX have been written, but we have been unable to inform the kernel of
the change, probably because it/they are in use.  As a result, the old
partition(s) will remain in use.  You should reboot now before making further
changes.
Ignore/Cancel? i
(parted)

The error is normal, and appears when you run parted as an ordinary user, so it is OK each time it appears to press “i” to ignore it. For the rest of this tutorial I will omit these errors from the output for brevity.

Make three partitions, a fat32 partition for the image itself that is 5% larger than the size of the ISO, a 1G ext4 partition for persistence, and an extra fat32 partition for the rest of the space. Put the extra partition first so that other OSes you might use the key with will be able to use it. Use relative positioning from the end of the device to make it easy to put all of the rest of the space in the first partition. Finally, flag the live image partition bootable.

(parted) mkpart primary fat32 1 -1897M
(parted) mkpart primary ext4 -1897M -897M
(parted) mkpart primary fat32 -897M -0
(parted) set 3 boot on
(parted) quit
Information: You may need to update /etc/fstab.

Unplug the USB key and plug it in again so that the kernel will re-read the updated partition table. If there were old filesystems on the key that were automounted, unmount them again. Now we’re ready to make the new filesystems.

$ umount /dev/sdX1
$ /sbin/mkdosfs -nEXTRA /dev/sdX1
mkdosfs 3.0.16 (01 Mar 2013)
$ /sbin/mkfs.ext4 -q -Lpersistence /dev/sdX2
$ /sbin/mkdosfs -nLXDE /dev/sdX3
mkdosfs 3.0.16 (01 Mar 2013)

Make the USB key bootable

Use install-mbr to install an MBR on the key and syslinux to install the bootloader to boot into your live image partition.

$ /sbin/install-mbr /dev/sdX
$ syslinux -i /dev/sdX3

Mount the partitions

Unplug the key and plug it in again so the new partitions will be automounted.

Observe where the partitions are mounted with df.

$ df
...
/dev/sdX1        6204568         4   6204564   1% /media/EXTRA
/dev/sdX3         831888         4    831884   1% /media/LXDE
/dev/sdX2         944120      1204    894124   1% /media/persistence

Extract the ISO contents to the key

To continue preparing this key as an unprivileged user, use p7zip to extract the ISO. You may alternatively mount the ISO loopback and extract it that way, but you must be root to do that.

$ cd /media/LXDE
$ 7z x ~/debian-live-7.0.0-amd64-lxde-desktop.iso
...
Extracting  live/filesystem.packages-remove
...

When live/filesystem.squashfs is extracted (right after live/filesystem.packages-remove) it will take the longest time of all of the files to extract, as it contains the whole live filesystem. Be patient and eventually it and all other files on the image will finish extracting.

...
Everything is Ok

Folders: 245
Files: 370
Size:       892183367
Compressed: 895483904

Modify the bootloader configuration files

The syslinux bootloader configuration directory and files within it are named isolinux when installed on an ISO. You need to rename the directory and two files changing isolinux to syslinux so the bootloader will find them on your fat32 live image partition.

$ mv isolinux syslinux
$ mv syslinux/isolinux.cfg syslinux/syslinux.cfg
$ mv syslinux/isolinux.bin syslinux/syslinux.bin

Enable full persistence

Next, append “ persistence” to the live boot parameters and turn on full persistence by putting “/ union” in a persistence.conf file in the persistence partition.

$ sed -i 's/\(append boot=.*\)$/\1 persistence/' syslinux/live.cfg
$ cd /media/persistence
$ echo / union > persistence.conf

Reboot into the live system

Now your USB key is ready to boot with full persistence enabled. Have fun!

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Debugging the installer on Debian Live

I’ve been using this process for debugging the installer while launched from a Debian Live desktop. Having a full live environment at your disposal during install is a boon to debugging because you don’t have to work within the constraints normally imposed upon you by the limited debian-installer environment. Caveat: running debian-installer from the debian-installer-launcher still has one or two unresolved issues, so unless you’re specifically working on live integration issues like I am, compare with a conventional d-i image install to gain the added confidence the install is the same in both environments.

There are no longer active maintainers working on debian-installer-launcher and live-installer, and I think it’s really important for wheezy to release with solid support for live installs, so I’ve been using this setup to try to solve #702335. So far, progress is slow because I’m new to this. If anyone is interested in collaborating in this work, give me a shout. I am SynrG @ irc.oftc.net and can be found on #debian-live and #debian-boot if you would like to drop in.

Overview:

  1. Use images/lxde-desktop config from live-images.git and build your own image with live-build >=3.0.1-1. Just add “-b hdd” in auto/config before starting your build, as having a read/writable image is handy for this exercise.
  2. Boot the live medium. You may prefer to do this in a VM for convenience, having prepared a blank virtual disk image as your target in advance.
  3. Make any small changes you want to the installer before launching it.  A quick hack I’ve used is to “sudo vi /usr/sbin/debian-installer-launcher” and near the end on the line after “prepare” right before “run”, open a new line and add “bash” so an interactive shell will be opened after the installer is extracted but before it is launched. For larger changes (e.g. inclusion of updated udebs, etc.) add them to your live image configuration before building as described in live-manual.
  4. Open two root terminals and do “debian-installer-launcher -t debug” in one and “tail -f /lib/live/installer/var/log/syslog” in the other. If you’ve added the hack from step 3, don’t forget to “exit” the interactive shell after making changes. Now you can watch debug output as you go through the steps of the installer. If you like, you may append additional boot prompt parameters (e.g. preseeds) to the debian-installer-launcher command.
  5. During the install, you may modify other parts of the unpacked installer under /lib/live/installer (e.g. to add ‘set -x’ to some scripts) prior to executing steps that would call them.
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Collaborative editing, the missing Vim feature (pentadactyl + etherpad?)

Do you wish, like I do, you could edit collaboratively in Vim? This feature is number 10 on the Vim voting page, so it seems I’m not alone. How about Pentadactyl coupled with any of the existing web-based collaborative editors, such as Etherpad? OK, so it’s not quite Vim, and there are some rough edges to this particular pairing, but I’m finding it’s good enough for my needs. It even gives me a Vim-like editing experience while other participants use the default Etherpad editor.

Yes, I know about whiteboard.debian.net, but for the past three years I have been using a single instance of Etherpad with my family to maintain a shopping list to which we all make contributions. First of all, that’s not a Debian activity, so to make the switch, I’d need to make a personal clone of the service for our personal use. But more importantly, we find Etherpad features such as colours for different participants and the timeline are just too useful to give up on. On the other hand, the less the web editor interferes with your web browser’s default textarea behaviour, the easier time Pentadactyl is going to have. Indeed, I asked on #pentadactyl @ irc.oftc.net about some problems I was having and I was told flat out that Pentadactyl does not work with graphical web editors. So, you may wish to use another web-based collaborative editor for this reason. That being said, I did learn a few things about helping Pentadactyl get along better with Etherpad, so if you would like to try it yourself, read on.

The key to getting started was to enter ‘text edit mode’ within the textarea with <C-t>. For the most part, this behaves like Vim ‘normal mode’. I am still learning, but many basic motion and editing keys behave just as they would in Vim. Fantastic!

However, the moment I tried to :undo I hit my first problem. Using the latest release version of Pentadactyl (1.0rc1 at time of writing), pressing "u" to :undo produced no visible result. I tried the latest daily build as well, and only saw a marginally more helpful "Node not found" error message displayed in the status area. But it turns out you can use ‘passthrough mode’ to use the textarea’s own undo. Just :tmap u <C-v><C-z> and we’re back in business again.

I’m still experimenting with this setup, so the jury’s still out on whether I’ll stick with it, or whether the remaining incompatibilities between Pentadactyl and Etherpad will drive me nuts. But it looks promising. Clearly, judicious use of :autocmd to always start in ‘text edit mode’ and bind that undo key whenever I enter the site will help make the experience even better. If you try it out yourself, I’d love to hear how things went for you. Or if you have found an even better solution that works for you, do share.

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Eee PC care at 2 years

In November 2007, we bought two of the first Eee PC netbooks available in North America: the model 4G in pearl white, one for me, and one for my wife. My plan was to start the Debian Eee PC project and get Debian working on them both which, thanks to the work of everyone on the team, has been a great success. Fast forward to February 2010, and they are still serving us well. Here is a list of hardware enhancements and issues over the past two years of continuous use:

Battery life

Asus claims 3.5hrs for the model 4G, though I don’t think we ever experienced anything better than 2.5 hrs with wifi in operation. Today, I’m down to something short of 2 hrs. If you consider the Lithium ion battery article on Wikipedia to be accurate, it is typical to permanently lose 20% capacity per year, so this sounds about right for the age of the battery.

Touchpad

The touchpad itself is fine. The buttons are not. They are hard to push and prone to become less responsive after a while, or to fail entirely. I now really have to bear down hard on my left button to make it work. Because the buttons are soldered to the motherboard, they would be hard to replace. Configuring the synaptics driver for tap-to-click is an acceptable workaround. Also, one of the first purchases we made was the Logitech VX Nano, one for each Eee, so most of the time now, we use our mice, falling back to the touchpad only when using a mouse is inconvenient due to space constraints (e.g. on the bus).

Keyboard

After two years of continuous use, both of our keyboards needed replacing. Some of the keys had been pounded flat and needed surgery (rubber springs sliced out of a scavenged Acer netbook keyboard and grafted on) to make them usable again. And aesthetically, the keyboards have really suffered, with a good percentage of the markings on the keycaps partially or completely eroded off.

Fortunately, for $3 plus $10 shipping each, new keyboards can be ordered from a Chinese e-Bay seller. But with the new keyboards, there is still the problem with excessive flex in the keyboard making some keys less responsive than others. I’m considering trying this hack to solve the problem.

Display

I have no complaints about the matte finish displays of either Eee. Both have stood up well. People tell me they don’t care for a 7″ display, but I find it bright, crisp and easy to get along with, so long as you maximize windows and increase font size as needed (e.g. for reading PDF books and magazines). When I really need the extra real estate, I just hook up an external monitor.

Fan

Some people complain about the noise of the fan, from the otherwise silent 4G (due to the lack of a hard drive) and seek ways to limit the amount of time the fan runs. We’ve never had that problem. However, if any plastic bits break off inside the Eee, they will eventually find their way to your fan and get wedged. This has happened twice: once in my wife’s Eee, and once in mine. Disassembly of the Eee to clear the blockage and get the fan running again was relatively painless both times.

Plastic bits

About those plastic bits: In my wife’s case, I think the bit was some extruded plastic from the molding that had broken off. In my case, it was a deteriorating plastic post which was holding the hinge in place. More about this later.

Sound

Unfortunately, the integrated sound seems to be particularly sensitive to heat. During both fan failures, sound cut out. On my wife’s system, it never fully recovered, and now only works on alternate Tuesdays, whereas on mine, after I unwedged the fan and brought the heat down, sound has functioned properly ever since. (Update: see my comments below on power adapters for an alternate theory about what killed sound.) We are waiting now for the delivery of a cheap ($1.42 including shipping, again from China) 3D Sound USB device which is reported to work on Linux. While some users complain about hum with this device, we’re cautiously optimistic that on the Eee it won’t be an issue. If it is, oh well, a buck and a half is a small gamble.

Update: It works! My wife is very happy. Money well spent.

Display hinge

The plastic posts that hold the anchors for the machine screws for the hinge are fragile. Three out of four of these posts in my Eee have shattered, leaving the left hinge to float freely. For the past two days I was distressed about how I could fix this. Based on some helpful suggestions from #eeepc @ irc.freenode.net, I had worked out a plan to rebuild one of the posts with two-part epoxy, sand it and the fractured stub of the post, and use cyanoacrylate glue to affix it to the case. It sounded like fiddly work for which I didn’t hold much hope of success. But this morning, I realized that the plastic in the bottom of the case was still sound, and that I could drop a screw into that hole, and with pliers, line up the anchor on the other side. This appears to work! I’ll handle that hinge with care, but it should do me until I eventually repurpose the machine to some daily use that is less stressful on the hinge than daily travel on the bus.

Update: Sadly, this broke on the weekend. The thin bit of plastic at the bottom of the hole just couldn’t take the stress. I’m planning a second attempt to fix it soon, using sturdier materials.

SSD and SDHC

Some people were initially worried that the limited write life an SSD meant that you needed to take special measures to avoid its premature death, which I have always regarded as a myth. Our 4G SSDs each have no swap space, and ext3 filesystems. At the two year point, there are no problems. I expect our SSDs to outlast the other components.

We did, however, eventually find the 4G to be a bit on the small side. We now each have Kingston 4G micro-SDHC cards for a bit of extra capacity for large media files and for some extra space for the apt cache. I recently priced the Lexan version of this card at $19 for a two-pack at Wal-mart, and these seem to work in the model 4G just as well (which seems to be an issue with this model — not all SDHC cards work).

Memory

We found the 512M that came with the 4G somewhat constraining. Without any swap space (so we could maximize the space available on the small SSD) we decided our systems really needed a memory upgrade. At the time, 2G didn’t seem overly expensive (though I no longer remember the exact price) so we splurged on 2G for each system, even though that was probably more than we needed.

Power adapter

When I first wrote this article, I forgot to mention the power adapter. The model 4G uses an unusual 9.5V power adapter for which it is hard to find a generic replacement. This unit is prone to fail in two places: in rare cases, (one out of 6 units that I have in some way assisted with: 3 of them mine, 3 belonging to others,) it will break at the wall plug end. The plug swivels into the unit for easy storage, but this adds a point of failure. More commonly, (in 3 out of six of the units,) the wires at the netbook plug end will fray due to stress on the non-angled cord, leading either to no connect, or to a short. In fact, since in the case of my wife’s adapter, the netbook end of the cable shorted, making the cable heat up and the system spontaneously shut down after a little while, we can’t say for sure whether the overheating of the Eee took out integrated sound, or whether this short did. On the one hand, I know for certain my own system, which never suffered a short, has responded to overheating by making the sound flaky, but it has never taken out sound completely. On the other hand, shorting the power cable can’t be very good for the Eee, so who knows, maybe that’s what ultimately killed my wife’s Eee’s sound.

This is where it helps to have soldering skills, or a friend who can do the repair for you. In my case, it was the latter. While I was waiting for a replacement adapter I had ordered, we also found on eeeuser.com part#s for replacement plugs and sleeves from Digikey, total cost $20 including shipping, 10 pieces each. Cutting off the bad plugs on three units and attaching the new was a quick, straightforward operation, and succeeded in two out of three cases. Having carefully checked the failed repair, we deduced that the failure in that unit was at the wall end, and we judged there was nothing further we could do to try to save it. Even the unit that had previously shorted was returned to perfect health and has been in operation trouble-free ever since.

Conclusion

After over two years of continuous use, the model 4G has held up well for a $400 system. We definitely feel we have received our money’s worth of value over that time. All of the problems we’ve experienced so far have been fixable at very little expense, and we expect them to last at least another year before we seriously consider replacing them. In the next several months, I plan to order a high capacity 8-cell 10400mAh battery for my own system so that I can enjoy a 5-6 hr run time. The purchase will be roughly $55 including shipping, the most expensive purchase for my system to date, but still well worth it to extend the 4G’s lifespan for another year or more.

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Bits from the Eee PC team, Spring 2009

Lenny well supported

We’re pleased that Lenny released with good support for the Eee PC and are now turning our efforts to make Squeeze even better, while continuing to provide support for our Lenny user base.  The standard Lenny installer can install Debian on all models of Eee and our custom installer provides the ability to install over wireless for almost every model (more about this later) from a very small image.  The latter continues to be our recommended install method, since in addition to being wireless-ready, the custom installer also handles a few other small eee-specific configuration chores to make as much as possible “just work” right after the install.

Solid mainstream support

We’ve made good on our promise to make Debian work on the Eee PC, not a derivative, many of which use a custom kernel instead of the stock kernel as we do and use a special desktop instead of our users’ favourites.  While we agree that some intriguing things can be done in these areas, it is no substitute for mainstream support.  Our users are better served by a solid foundation than specialised modifications that limit their choices.  We want them to be able to enjoy the freedom to mold Debian, the universal OS, into whatever suits them best.

Squeeze support started

Work is well underway on supporting all Eee models in Squeeze.  For months, several team members have been experimenting with new kernels, producing support for them in eeepc-acpi-scripts.  The current release of this key package (version 1.1.0) supports Linux 2.6.29 and contains enhancements for wifi, sound hotkeys, bluetooth, external displays and OSD.

Squeeze will support wired & wifi on all current models

With the appearance of 2.6.29 in Sid, all ethernet and wifi cards used in all models of Eee today are supportable without the need for out-of-kernel or non-free drivers.  Madwifi is replaced by the free ath5k driver, the non-free rt2860 package is replaced by mainstream kernel support, (though it still requires non-free firmware provided separately by firmware-linux — for now in 2.6.29, the firmware is included in the kernel, but that is a bug fixed in 2.6.30,) rtl8187se is included, making it possible now for us to support the model 701SD, and ath9k is included, making full support for newer models such as the 1000HE possible.

Lenny backports and live demo

All of these changes can be enjoyed today by Lenny users.  Just add Daniel Baumann’s Lenny kernel backport repository and then install the 2.6.29 kernel and an updated acpid.  See our upgrade howto for details.  You can try a small (less than 256M) demo of this configuration by downloading beta 2 of our Live USB image.

Accessibility

Late last year, we discussed how to make it easier for the blind to install Debian unassisted on their Eee PCs.  As it was a simple change, we now include brltty in the custom installer, but we understand that some users also need software synthesized text-to-speech, something for which there is no support yet in the standard Debian-installer.  We understand this isn’t an easy thing to fix, but hope someone will rise to the challenge.

Growing team of developers

We welcome Darren Salt and Raphael Geissert to the team this year.  Both have been actively making contributions to the eeepc-acpi-scripts package over the past months, fixing some outstanding bugs and readying it to handle changes in more recent kernel releases.

Moved eeepc.debian.net to new hosting

Nico Golde, who hosted eeepc.debian.net for the first year development, has turned his focus to other areas of Debian.  Glenn Saberton has stepped in to provide a new home for it.  We thank them both for their efforts and for a smooth, uneventful transition from one host to the other.

Size of user community

Speaking of the move, earlier this year, Glenn shared with us some interesting archive traffic statistics that give us a rough idea how many users we have.  For the months of December and January, after factoring out bot hits, we were seeing about 300,000 hits from 15,000 unique users per month.  The site handles roughly 60G of traffic per month, most of that from thousands of downloads of our custom installer image.  It’s hard to draw any firm conclusions about the size of our user base from these stats, as many users may be on dynamic IP numbers, inflating the numbers, but we can conservatively say we have at least 5000 users.  Other interesting statistics are that we have anywhere up to 80 users at any given time on our irc channel and over 250 users on the mailing list.

Help wanted

The Asus Eee PC line continues to expand, with 24 models listed so far.  It is a challenge to keep up support for all of them.  We’re encouraged to see Asus choose a new b/g/n wifi chipset for their 1002HA that is supported by a DFSG free driver — ath9k in this case.  It appears that the new Atom N280-based 1000HE uses the same chipset as well (though be careful: I know of at least one user who bought a 1000HE in Argentina expecting it to have this chipset and was disappointed to find it had the Ralink chipset instead, we guess because of availability).  If this trend continues, we’ll be that much closer to our goal of full support for Squeeze main.  As it stands, we’re already as close as we can get given the state of rt2860 and no prospect on the horizon for replacing the non-free firmware.

If you would like to help us out in any way, whether by testing, debugging, patching, or improving our documentation, get in touch with our team.  We rely on your feedback to keep Lenny in good shape and work towards making Squeeze even better for all users of Debian on the Eee PC.

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Involve kids in free software development through play

Giving up on a position within a free software project when you know you’re no longer managing to do an effective job is a wonderfully liberating experience. Now that I have started to talk with Miriam Ruiz about handing over the Debian Jr. project, I can stop worrying about the leadership task and just have fun with it.

I can always count on Miriam for recommendations for games in Debian my kids may enjoy, as she has a passion for finding good games to package for Debian, and in particular, games for children. Over the past few weeks we’ve had some fun with her picks. At the same time, I always have Debian Jr. in mind. How can we ensure kids can have the most fun with this? How do we equip their guides to help them?

What we’ve done with each new piece of software is to find a quiet time when one or more of the children can start playing with it on their own while we watch, offering such guidance as they need, but for the most part just letting them loose with it. Each wrinkle of the brow, each impetuous thump of the mouse, every illuminated grin and exclamation of delight is noted. We try to see what frustrates or pleases our kids and discuss it both with them and the Debian maintainers and upstream developers. This is an excercise we’ve managed to pull off without being overly intrusive and the results have been well worth the effort.

Using a few of Miriam’s picks we tried this week, we were able to draw their play into the free software development process. Here’s a brief summary of those sessions:

Platinum Arts Sandbox puts into children’s hands the ability to role play in a 3D world and edit that world using simplified controls. The expressions on the faces of our kids as they played were priceless: both the ups and the downs. I wanted to capture this on video and share it. After having established a rapport with upstream, we took a 20 minute clip of one of our play sessions and gave a copy to them to use to help further their work. Here is the edited result. They were very pleased to have that kind of feedback and found the video valuable for determining where the software still needed improvement and to notice which aspects particularly pleased the children.

I happen to know that Hex-a-hop is one of Miriam’s personal favourites. We have a household full of puzzle-lovers so this puzzle game was an instant hit. While on irc on #debian-jr with Miriam we relayed in real-time some of the reactions as they played this and a handful of her other picks. This gave her some confirmation of areas she knew needed work as well as inspiration for upcoming releases of these packages.

During this play session, which also included StegaVorto, kartofel, Anagramarama, Funny Boat and Vodovod, my youngest girl, age 7, plunked down on the couch next to me as her 10-year-old sister played. Then she started to notice I was typing what people in the livingroom were saying and doing on irc. She took a mild affront to me copying her own words and actions, so I decided it would be better to let her participate so she would feel included. At this point, I started playing secretary for her, typing what she dictated to me while she read the responses from the display. Later, I just handed her the keyboard so she could type and read the responses on her own. She was still at it long past bedtime and it was with some reluctance that she finally gave up the keyboard. We all had a lot of fun and look forward to doing this again.

We are particularly careful with privacy, taking care to share pictures, videos, and other personal details only so far as we believe it does not put our children at risk. Also, we need to ensure we observe in a way that is welcome and doesn’t interfere with their enjoyment. But with a little bit of prudence and a practiced eye and ear for what increases or diminishes enjoyment of the software, we can involve our children directly in the free software development process. I commend to anyone who has the privilege to share free software with children to use this method to communicate with maintainers and developers, increasing your own enjoyment of the software in the process and that of children and their guides everywhere.

Update: A quote from this article has made it to Slashdot. Although many of the comments seem to miss my point entirely, it’s nice to get a wider audience.

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Wifi roaming on the move

Preface: legal stuff

Depending on where you live, use of random open wifi networks might be considered illegal. Although I know of no law in my country against doing this, where you live, things may be different, so educate yourself before following my example.

Wifi roaming on the move

For the past year I have used my Eee PC on the metro transit bus, as it is the perfect size for this. When I can, I take advantage of open networks to connect back home. In this article I will show how you can actually use such access, will recommend which software works best and will explain how to set it up.

So, what can I really do with the net while in motion?

How about irc? No kidding! This shell one-liner does the job:

while ! ssh -t 10.9.8.7 'screen -UDr' 2>/dev/null ; do echo -n "." ; sleep .1 ; done

We’re concerned about privacy and security on other people’s networks, so we use ssh. Inside that screen session, keep irssi running for a continuous irc presence. Every 10th of a second, the script tries to resume your session. Once a the net passes by, typing “[Enter]~.” drops you back out to retry again. The row of dots serves as a progress bar. If you want to get fancy, you could replace that with an ASCII ‘spinner’. I leave that as an exercise for the reader. 🙂

Come on, is that really usable?

Certainly. As the good folks on #eeepc at irc.freenode.net and #debian-eeepc at irc.oftc.net can attest, even a half dozen brief connections can be enough to provide tech support, rough out some development ideas, or just carry on some friendly chat. If your spouse or housemate is online too, it can even help you make some last-minute grocery-list changes. 🙂 While the script is working, enjoy some offline things such as blogging, reading a cached Planet Debian feed or a PDF book.

OK, so what else do I need to make it work?

Well, you’ve seen so far we need on a server:

  • openssh-server
  • screen
  • irssi

On the Eee, you should also have:

  • openssh-client
  • wpasupplicant
  • gnome-terminal

But what do I need wpasupplicant for if I only use open networks?

Well, wpasupplicant is really handy for fast control of networks in Roaming Mode (as per /usr/share/doc/wpasupplicant/README.modes.gz). A GUI is just too slow. For example, you may need to filter out ‘junk’ open wifi nets: pay-per-use hotspots or nets that hide their name. You’ll not only want a “catch-all” stanza for any open network, but also a number of the most commonly found default network names, e.g.

# Catch-all; associates with any open network:
network={
     key_mgmt=NONE
}
# Commonly found default network names:
network={
     ssid="default"
     key_mgmt=NONE
}
network={
     ssid="linksys"
     key_mgmt=NONE
}
# etc. by watching scan_results closely you'll find several more

While the connect script is running, keep a separate tab open in gnome-terminal for wpa_cli. Use ‘disable_network 0’ to drop the catch-all and let the other stanzas kick in and ‘enable_network 0’ after filtering is no longer needed.

Isn’t it really slow to get connected?

Without some tweaks, yes. But here are a few things I have found by trial and error that help.

One issue is that dhclient takes too long to retry, so you drop the delay between retries back to 1 second in /etc/dhcp3/dhclient.conf:

backoff-cutoff 1;
initial-interval 1;

If the signal is very weak, you’ll want the transmit power turned up to the maximum value for your hardware. For the Eee PC 4G this is 50mW, so you set this in /etc/network/interfaces for ath0, your wireless interface:

wireless-txpower 50mW

Finally, while you’re in motion you are constantly leaving no-longer-usable access points behind. The driver needs to discard them as quickly as possible and scan for new ones. So again in /etc/network/interfaces for ath0, you bring the default scanvalid 60 seconds down to 10 with:

pre-up /sbin/iwpriv ath0 scanvalid 10

Conclusion

The netbook has changed how we use the net. Now that we can take it everywhere, we either pay through the nose for expensive cell network access or else use the patchy wifi coverage blanketing most urban areas. A few lucky cities have such things as municipal wifi nets, but the rest of us have to scrape what access we can wherever we go. You are now equipped to try this out on the bus. If you find any other tips that can help, I’d love to hear from you.

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Bits from the Debian Eee PC team, autumn 2008

Some brief highlights of the last three months of Debian Eee PC development.

Thermal and ACPI breakage resolved in 2.6.26-7

We’re pleased to see that in the upload to Sid of linux-image-2.6.26-1-686 version 2.6.26-7, the pair of 2.6.26 bugs we’ve been tracking that have made it difficult for Eee users to upgrade their systems have been resolved. Since then 2.6.26-8 has been uploaded and is expected to enter Lenny this week due to a freeze exception. Once the new kernel has migrated we will move quickly to build and release a new installer that includes it.

Ath5k wifi works on Eee PC in Linux 2.6.27

Jean-Christophe reports that ath5k works in Linux 2.6.27 on the Eee PC 701, and just needs a small patch to work with our eeepc-acpi-scripts package. This is good news for those of us with models 701, 900, 900A and 1000HD who have been wanting to get off of the non-free Madwifi drivers and onto DFSG free drivers.

New Eee PC model 701SD wifi support in the works

Users of the new Eee PC Model 701SD have just started showing up looking for support in mainstream Linux distros. Martin Filtenborg confirmed using our Eee PC Live image with the GPL’d rtl8187se driver from Realtek that we can at least use it to connect to an unencrypted AP, get an IP address and ping other hosts.

Of course, it is one thing to have a working vendor-supplied driver and quite another to have mainstream support. We’ll make do with what we have now, but will be seeking a mainstream solution as soon as possible.

We’re seeking more testers and developers to work on this. To date, an ITP has not been filed, as it is not yet clear who is going to carry this work forward.

Chasing the 5 second boot

An interesting discussion on Arjan van de Ven and
Auke Kok’s work to get an Eee 901 to boot in 5 seconds
took place this month. While the Debian Eee PC team is not making work on this a priority, we’ll keep an eye on it to see if Debian can incorporate some or all of the techniques they used so that our users can benefit without making radical changes to their systems.

Working towards mainstream support for rt2860

Our filing of an ITP for rt2860 (the wifi driver for models 901, 1000 and 1000H) was followed by discussion about how to separate out the GPL’d driver from the embedded non-free firmware so that it can at least go into contrib. Glenn Saberton has been working on rewriting the build system around kbuild and separating out the firmware.

Numerous improvements to ACPI scripts

Since my last progress report, there have been numerous improvements to the eeepc-acpi-scripts package to deal with all of the various models we now support and make the scripts more robust and flexible. Check out the changelog for details.

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Bits from the Debian Eee PC team, summer 2008

As always, we’re doing lots of interesting and significant things and have more good ideas than we have people to do the work.  If you have an Eee PC or are planning to get one, or are otherwise interested in our work, some of which has uses beyond just the Eee, here are some highlights:

Earliest Eee models supported in Lenny

Lenny will release with the atl2 ethernet driver and the non-free madwifi-source now works with the earliest Eee models as well, so our patched version is no longer needed.  This means Lenny will work with all of the earliest models of the Eee PC: 701 (2G and 4G surf, 4G, 8G) and 900! All we need now for full support in Lenny is to replace the non-free wireless driver with the free ath5k driver when it is ready.

Free drivers

Nick Kossifidis has submitted patches on linux-wireless supporting the Eee models currently supported only by the non-free madwifi in ath5k.  This means we’ll soon realize our goal of a completely DFSG free system for the earliest models of the Eee.  By 2.6.27, or at the latest 2.6.28, these models will be supported.  Then we will see about making a patch to support whichever kernel makes it into Lenny.

New models

Model 901, 1000 and 1000H users are now able to install using the atl1e ethernet driver from eeepc.debian.net.  Support for wireless and other aspects of the new hardware will follow soon.  The debian-kernel team was prompt to add atl1e to 2.6.26 which has just been uploaded to sid.  We hope 2.6.26 makes it into Lenny.

Wireless installer

Glenn Saberton has been doing an upstanding job adding wireless support to our custom Debian-installer.  We have supported WEP authentication for several releases, now, and a beta version supports WPA.  Glenn is also making progress with these patches upstream so that non-Eee Debian users will benefit from our work.

LXDE is in Lenny

LXDE has entered Lenny, thanks to Andrew Lee.  It is a quite lightweight desktop environment that is made with the Eee PC in mind.

Live images

Two flavours of Debian-live USB images are available: a demo of the LXDE desktop and a minimal console-only image for rescue/backup.  The images are still in alpha stage of development.  If you’d like to help, give us a shout.

More interesting things are planned for the future that benefit Debian as a whole.  With a small amount of work patching live-helper, anyone will be able to make a live image that includes a customized Debian-installer.

Mobile device initiative

This month on debian-devel, there was some interesting discussion about Debian support for the Intel Atom processor and a possible mobile net device initiative.  That’s something we could get behind, if anything comes of it.

Wiki translation

Robert Epprecht has been keeping the German wiki translation in good shape, but we could always use some more help with any of the translations.

New members welcome

If you’d like to join us, check out our site at http://wiki.debian.org/DebianEeePC and drop us a note on our list or join our irc channel and talk to us about what you’d like to do.

 

 

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