Category Archives: Hardware

Computers and electronic devices.

ASRock X99 Extreme4 running GNU/Linux

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I picked up an old ASRock X99 Extreme4 motherboard from my workplace during an office move a while back which was no longer required by the company. Naturally I put Debian GNU/Linux on it!

It does not use ECC RAM, and I would always see these annoying messages in the kernel logs:

EDAC sbridge: Seeking for: PCI ID XXXX:XXXX

This would be repeated 33 times for different PCI IDs, all of which were repeated 12 times each (for each CPU thread it seems), resulting in 396 such kernel messages for every boot!

Further, each CPU thread would print the following error in red:

EDAC sbridge: CPU SrcID #0, Ha #0, Channel #0 has DIMMs, but ECC is disabled
EDAC sbridge: Couldn’t find mci handler
EDAC sbridge: Failed to register device with error -19.

Clearly the system is attempting to work with ECC which is not configured on this system. Having ECC usage fail is expected, but the logs are very annoying. They get in the way of any messages which might actually be important.

Fortunately, after some trial and error, this was the solution which made all of these pointless messages go away:

echo "blacklist sb_edac" > /etc/modprobe.d/edac-blacklist.conf

If you find yourself in a similar situation with a different motherboard, you can blacklist all edac-related kernel modules used by the currently running kernel by running the following as root (all as one line):

for i in $(find "/lib/modules/$(uname -r)" -type f -iname '*edac*' -exec basename {} \; | cut -d '.' -f 1) ; do echo blacklist ${i} ; done > /etc/modprobe.d/edac-blacklist.conf

Once you have created an edac-blacklist.conf file with one of the above commands, you can have it take effect by regenerating your initramfs file like so (again, as root):

update-initramfs -k all -u

Hopefully someone else finds this information useful.

HP 14-AF113AU 14″ Notebook initial impressions

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Last week, I was unfortunate enough to have my Asus UX31A laptop stolen from my apartment. Fortunately I use LUKS full disk encryption for all my machines, so I don’t need to worry much about data loss, but it’s still quite infuriating to be in this situation. I’m on call 24×7, and I need a reliable light-weight machine I can take with me anywhere so I can quickly react to production IaaS and application issues should they arise.

Previously I used a AMD E-350-based Sony Vaio laptop which I acquired in 2011 and upgraded the RAM to 8Gb and swapped out the HDD for an SSD. Unfortunately due to the lack of AES support, running LUKS on it was painful. Ultimately I reached the breaking point this year when my workplace required me to run more and more JS-heavy web apps such as Slack and Trello, and then asked me to log into Slack in the event of an outage to keep them updated. Previously I’d just fire up Pidgin and connect to the work-hosted XMPP service in just a few seconds, but Slack (even with a dedicated client such as ScudCloud) would take longer to load and connect than the entire time it took to boot the laptop to the desktop – all the while making the machine too slow to do anything else! Ridiculous! But perhaps that’s a topic for another post.

For a time I was considering the MSI GS30 Shadow, but ultimately my spouse decided to hand me down the UX31A which otherwise wasn’t getting much use. With that stolen, and the AMD E-350 too slow, I found myself once again in the market for a new laptop – only without much of a budget since it wasn’t something I was planning for. :/

You have probably inferred from the title of this post that I eventually decided on the HP 14-AF113AU, so I’ll detail how I came to that conclusion. My priorities were (roughly in order):

1. Works well with free software, such as GNU/Linux.
2. Lightweight. I need to carry this with me anywhere and everywhere. If I go to the supermarket, it’s in my backpack. If I use it to work, I’m carrying it in my bike pannier.
3. No bigger than 14″. It’s unlikely anything bigger than that would fit in my bike pannier, and I didn’t want to risk it.
4. CPU power (preferably 4 cores). Must have extensions for AES support, as the lack of AES was one of the reasons my AMD E-350 was so slow. I wasn’t about to make that mistake again.
5. Cheap! I was hoping for something under AU$500. I could probably have stretched this to $600 if there was a significant advantage in doing so, but under $500 was the goal.
6. Upgradeable RAM, storage, wireless.
7. Screen resolution.
8. Bluetooth. I generally tether to my phone in case of emergencies when I’m out, and Bluetooth is my preferred way to do that. It uses less power than Wifi, which is important if I don’t have a spare charger with me. A lot of wireless headphones also rely on Bluetooth these days, and I hate needing to use dongles.
9. USB 3. USB 2 is just too slow when transferring data to external SSD devices.
10. At least 3 USB ports. It wouldn’t matter much for use on the go, but having an external keyboard, mouse and room for at at least one USB drive would be ideal.
11. Gigabit Ethernet, with the RJ-45 port built-in (as opposed to a USB dongle). As an administrator, I have to troubleshoot patch Ethernet cabling every now and then, and having to bring a set of dongles everywhere just in case proved to be one of the major annoyances of the UX31A.
12. Taiwanese brand. American branded machines have a tendency to be dumbed down to the point of being useless – particularly in the BIOS. Contrast that to MSY, Asus, Gigabyte, etc and you’ve have a plethora of options and features. American brands also in my option/experience (especially Dell) seem to have a greater tendency to rely on Windows software to make the hardware work or to install firmware upgrades – an issue I’ve yet to run into with Taiwanese branded hardware. Last but not least, American brands have a tendency to require same-brand or approved hardware for compatibility. This includes memory modules (Apple), wireless cards (HP), etc. Taiwanese brands never pull that crap – at least not that I’ve ever encountered.

Things I didn’t want to deal with included:

1. Dead or stuck pixels.
2. Low resolution.
3. Dongles to connect to an external monitor.
4. Ordering hardware. I wanted something I could grab off the shelf at a local store, since I wanted something immediately and I don’t trust items posted to me directly. We know the NSA (for example) intercepts computer hardware and install bugs that are heat-injected into the plastic (making it hard to spot even if disassembled and you know what to look for), so my policy is to only purchase hardware that I can buy off the shelf with no advanced notice. It has the added bonus of supporting local businesses.

Things I didn’t care about included:
1. Size. As long as the laptop fits in my backpack and bike pannier and is easy to carry and lightweight, the laptop could be 7″ for all I cared.
2. The operating system. I was going to replace it with Debian GNU/Linux or something anyway. Obviously it would be best to not be paying for something I wasn’t going to use.
3. Optical drives. I’d likely never need to use one, the main exception being the occasional blu-ray disc (which I likely wouldn’t get for the price range I was looking at). An internal drive would unnecessarily add weight.
4. The hard drive size (assuming it was replaceable). For the price I wasn’t expecting an SSD, and the plan was to pull the SSD out of my old Sony E-350 if possible.

All things considered, this HP model did reasonably well at meeting my requirements. It’s just under 2kg (and 2kg is where I draw the line). I’d rather not it not have an optical drive and be ~300g less, but I decided it to be acceptable. Interestingly, lighter laptops seem to be either very cheap (and too weak to be much of an upgrade over the E-350), or quite expensive.

As mentioned, I care more about screen resolution than screen size (provided the screen is no bigger than 14″). Sadly the HP only has a resolution of 1366×768, and this is very hard to deal with to be honest. Having gotten quite used to the 1920×1080 resolution of the UX31A (which has a smaller 13.3″ panel), the HP screen looks absolutely awful. Unfortunately, the sales guy said FHD laptop resolutions only started at around the AU$1300 price bracket, which was more than double what I could possibly spend. It’s doubly unfortunate that the screen is glossy, and I’d much prefer a matte finish. I don’t need a mirror for a screen!

JB Hi-Fi advertises an asking price of $498, however I was able to get the sales guy to bring that down a bit to $484. That probably made this the cheapest quad-core laptop of those that are upgradeable. How did I know it was upgradeable? The mechanical HDD is generally a dead giveaway. Sure the sales guy said it couldn’t be upgraded due to not having a back panel section that could be unscrewed, but I suspected I could still do it by disassembling the entire thing – and I was right! As an aside, I was also pleasantly surprised to find a second empty RAM slot – potentially allowing me to upgrade from 4Gb to 16Gb!

The sales guy informed me that this had Gigabit Ethernet, but it doesn’t. Based on the output of the lspci command, it uses a RTL8101E/RTL8102E PCI Express Fast Ethernet controller. Not a deal-breaker, but quite disappointing. There’s no excuse for not having Gigabit on even the cheapest of laptops – if you’re going to add a RJ-45 Ethernet port anyway, make it useful please! As it stands, the 802.11n wireless is probably faster in general – although that remains to be seen.

The AF113AU does have a USB 3 port, and two USB 2 ports. It’s disappointing that all ports aren’t USB 3, as one has to remember which port is which. Unfortunately HP decided not to bother following convention by marking that port blue, so I had to look through the manual to figure it out.

I failed to get a Taiwanese brand such as Asus or Gigabyte, but hopefully HP doesn’t give me too much trouble. Perhaps the days of HP white-listing wireless cards are over? I’ll probably find out eventually, as the module included uses a Broadcom BCM43142 802.11b/g/n chipset – quite painful to setup. See here for a peek at a guide, but basically it appears to require non-free heavily-restricted firmware to function. The firmware is not freely distributed, so you need to use a script to download a file and extract the firmware files. Ugh! Unfortunately I know of no wireless/bluetooth combo module that’s 100% free software friendly, and I need Bluetooth to tether to my phone during emergencies.

I was lucky to have no dead or stuck pixels on this machine. I say “lucky” because apparently you need at least 3 stuck pixels before you are eligible to return the laptop under warranty, and I was not given the option to inspect the screen before purchase.

The machine requires no dongles to operate. All supported video and data connectors are built-in, which is ideal. I would rather have a laptop that’s 5mm wider and not require dongles do connect everything. It’s also surprising that the machine has a built-in DVD burner. This is absent in the product page image. The drive can easily be replaced with something else (such as a blue-ray drive or an empty caddy) by undoing a single screw and sliding the drive out, however one would have to research which drives would be compatible with the slot.

Another surprise was the size of the 500G Seagate HDD – the thinnest I’ve seen to date. The Corsair Force 3 SSD I replaced it with is about 1 or maybe 2 mm taller, but fortunately still fits (just).

Being an A4-5000 APU, the laptop sports Radeon HD 8330 graphics (which uses the radeonsi Mesa driver) and should offer reasonable performance for the price. So I find it odd that the machine doesn’t have an AMD logo on it anywhere. All Intel machines in the store seemed to have an Intel logo – including machines that weren’t an Atom/i3/i5/i7. It’s as if HP was ashamed of the APU in this cheap laptop, but there’s no reason for it that I can immediately see. Perhaps it doesn’t run Windows 10 (which it came with) so great? Weird.

Well, I wouldn’t know anyway – I swapped the HDDs before I ever booted the 500Gb. Then I backed up the perfectly clean factory default image to an external backup drive, which I’ll later compress, split and burn it to a set of DVDs – good to restore to its original state if ever I need to return the machine under warranty. I’ve been following this same procedure for my last few laptop purchases. Finally I wiped the 500Gb drive and put it into my old Sony (as perhaps one day I’ll find a use for it).

The keyboard is surprisingly nice to type on, with good feedback that a key has registered. Normally I use mechanical keyboards which are amazing, but the HP keyboard wasn’t too bad for what it is. Home/End/Page Up/Page Down/Insert/Delete/Print Screen are all dedicated keys, with fn shortcuts being reserved for non-standard keys such as multimedia buttons, backlight and volume adjustments and wireless and external monitor toggle switches. I feel this was a wise move by the people at HP, as it was always annoying on other machines having to remember the correct fn+button key combinations to navigate documents (for example). One thing I didn’t like about the keyboard was the decision to make the up/down navigation keys half-size, and the left/right keys full size. This just feels weird, unnatural, and I keep pressing the wrong buttons. HP had plenty of space to make all of the buttons full-size if they wanted to, but it feels like they took a page from Apple’s play-book and decided on aesthetics over practicality (but even Apple makes the arrow keys consistent at half-size at least!).

While I’ve yet to test the SD card reader, HDMI and VGA outputs, optical drive and webcam, everything seems to be working (with a bit of effort in the case of the Broadcom wireless chipset) and I’m reasonably satisfied. If the wireless chipset didn’t need such a horrible proprietary firmware blob, the Ethernet was Gigabit, the optical drive was blu-ray (or otherwise didn’t exist), the laptop was easier to upgrade and the screen was slightly better… oh and obviously if GNU/Linux was an option (or at least if Windows was optional)… this would be one really neat machine. But it’s not horrible. Despite the flaws, I’m at least impressed with the price. I may write a review after I’ve used it for a while and put it through its paces.

How to replace LightDM with XDM in Wheezy

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My machine is an Asus G55VW laptop, and it seems to have a very annoying UEFI or Nvidia driver bug. Even under Windows (which the laptop came with), everybody with this model is experiencing odd behaviour – the laptop will fail to detect the display properly in certain situations and attempt to output the screen to an external monitor – even if nothing is connected! Under Windows 8.1, this means the login screen isn’t displayed, and one must press Meta+P, hit the down arrow once or twice, and press enter (and do this until the internal laptop screen is activated). It’s absolutely horrible, and has only showed itself in the Windows world upon upgrading to Windows 8.1.

On Debian with LightDM however, I have experienced what I believe is this same issue (based on Xorg log file analysis) ever since I brought home the machine. Unlike Windows, I can login okay. However logging out of XFCE to the LightDM display manager causes the internal laptop screen to not be detected correctly during the switch. The result is a blank screen, and LightDM has no way (AFAICT) to switch display output via a shortcut when it’s already running. Further, it even prevents switching to a virtual console as no image will reappear if I hit Ctrl+Alt+F1 for example (which shouldn’t ever happen without explicitly disabling it in the Xorg config at least, which I certainly haven’t). The only option in such a situation is to switch to a virtual console and blindly hit Ctrl+Alt+Del and wait for the UEFI screen to appear.

Until recently (when Windows was upgraded to 8.1 and showed similar symptoms), I had always attributed this behaviour to a bug in Wheezy (since I purchased the laptop around the time Wheezy was being marked as stable so it could not have been tested on this model) and assumed it would be solved in time with Jessie, but now I’m not so sure. Rebooting the machine is very quick (the longest part easily being the lengthy passphrase required for cryptsetup) – quick enough that I’ve never bothered getting to the bottom of it, particularly since I can generally avoid hitting the problem in the first place since I’m so familiar now with what triggers it. However now I’m seeing such odd and annoying behaviour from both operating systems, it’s time to do something about it.

The only reliable way to avoid this is to activate CSM in the UEFI (to mimic BIOS functionality), but that has a number of drawbacks. The boot output resolution is restricted to VESA modes, which look horrible on a 1920×1080 display (especially when UEFI detects the resolution perfectly and looks beautiful). It also means I can’t use the rEFInd boot manager, which I now much prefer over GRUB on desktops and laptops. CSM also prevents enabling “Fast Boot” in the BIOS, which introduces a small but unnecessary delay. Indeed, enabling CSM feels like a significant step backwards, so I will try to avoid that wherever possible.

I’ve tried GDM3 temporarily, and that had the same issue at first. However I found that pressing fn+F8 (the LCD/monitor switching/toggle button) surprisingly worked and brought the picture back so I could see the login prompt. It even seemed to remember this setting somehow as I was never able to reproduce the issue with GDM3 after that. I thought that was the end of this dilemma and I could get back to doing something else. Unfortunately GDM3 had other issues.

Firstly, upon wearing headphones during login I was able to hear my laptop internal microphone was active via a loud hissing noise, and confirmed this by tapping the mic. I could find no way to turn this off, and could not think of any reason why GDM3 would be doing that. Secondly, I didn’t like the user accounts listed for selection. I wanted to type my username, as there is no reason to make the login name unnecessarily obvious. There was an option in the GDM theme config to allow this, but it wasn’t reliable. If I started entering my username and hit Escape or Ctrl+C (with the expectation that I could clear the box in the event of a typo), the login window would disappear completely and I’d have to reboot. Yuck!

But the worst issue of all, GDM3 was just too slow to keep up with my typing speed! I would type in my username, hit enter or tab, and then start typing in my password. Only the password would be missing the first few characters since the password box had not properly appeared yet. Even after all of that, there was a noticeable delay in launching my XFCE desktop. I can only imagine what it was doing with those CPU cycles.

So looking around at other display managers packaged in Wheezy, I found two suitable options – SLiM, and XDM. I didn’t know much about SLiM. I knew XDM was about as bare-bones as one could get, I knew it was fast, and I knew it required manually typing the username… it seemed to be the way to go, so I set out to make that happen.

$ sudo apt-get install xdm

I selected XDM to be my default login manager, rebooted, and there it was in all its glory. There were some things missing however – no X session manager list to choose from (which is perfectly fine), but also no shutdown and reboot options. I could live without those, although I still expected it would be a minor inconvenience. I was happy with the speed of the prompts – it felt slightly quicker than LightDM (that is, probably no perceivable delay). However XFCE spent about 20 seconds to appear. When it had finally loaded, some issues were encountered. For one thing, USB mounting wasn’t working. Manually clicking the mount button in Nautilus caused a “Not authorized” error to be displayed, with no hint as to why. The USB drives didn’t automatically mount via my usb_mass_mount.sh script either. I eventually noticed that even Network Manager wasn’t working!

Was all of this because I was using XDM? Some quick web searches for “Debian xfce xdm” indicated as such. Was it worth trying to fix it? I logged out of XFCE (observing as I went that even the reboot, shutdown, suspend and hibernate options were either missing or greyed out) and XDM continued to output to the correct monitor. Whatever this issue is with my model of laptop, XDM is not affected. With this and it’s impressive text entry speed, I decided these XDM issues were worth looking into.

What followed was a lot of careful analysis of the scripts under /etc/X11/Xsession.d/, and much research into what was causing this. Essentially, this can all be fixed with two or three minor changes – but they are amazingly difficult to figure out if you’ve never looked into the related technologies before.

PAM
In /etc/pam.d/common-session at the bottom of the file, there is the line “session optional pam_ck_connector.so nox11“. From the pam_ck_connector(8) man page, the nox11 argument tells the PAM module to not create a session if PAM specifies an X11 display instead of a /dev/tty terminal. I guess the assumption is that the display manager will handle this automatically, but XDM is too primitive to have ConsoleKit support. Hence remove that nox11 bit from the line. I actually like to copy the line, modify the copied line and then comment out the original, so such changes are slightly more obvious and easier to undo if I ever need to revert. Alternatively, take a backup. :)

Xsession
Our session needs to be started with /usr/bin/ck-launch-session. This is supposed to happen from /etc/X11/Xsession.d/90consolekit when it’s required, but it’s broken and needs to be fixed. There are a few ways to do this. Ideally I would have found a way to just bypass this script entirely (replacing the functionality with something in my home directory) but any fix would involve some kind of modification under /etc/X11 somewhere that I figured it best to just fix this at the root of the problem. Here is my patch:

--- 90consolekit.orig	2015-02-04 17:42:07.549621276 +0800
+++ 90consolekit	2015-02-04 17:41:25.021379155 +0800
@@ -24,9 +24,17 @@ is_on_console() {
 	fi
 }
 
+is_xdm() {
+	if [ "$(pgrep -cfx /usr/bin/xdm)" -ge 1 ] ; then
+		return 0
+	else
+		return 1
+	fi
+}
+
 # gdm already creates a CK session for us, so do not run the expensive D-Bus
 # calls if we have $GDMSESSION
 if [ -z "$GDMSESSION" ] && [ -x "$CK_LAUNCH_SESSION" ] && \
- ( [ -z "$XDG_SESSION_COOKIE" ] || is_on_console ) ; then
+ ( [ -z "$XDG_SESSION_COOKIE" ] || is_on_console || is_xdm ) ; then
     STARTUP="$CK_LAUNCH_SESSION $STARTUP"
 fi

Seems to do the job. Doesn’t break compatibility with startx (presumably – my laptop display doesn’t seem to work with that either so can’t verify) or other display managers since it specifically tests to see if XDM is running.

usb_mass_mount.sh
My lovely USB automatic mount script has been intermittently failing since switching to XDM, and it wasn’t immediately obvious why since it only failed during login and could not be reproduced afterwards. I quickly discovered that the udisks command was also actually returning a Not authorized error (the same as was observed from Nautilus prior to the above fixes) – something I did not encounter under LightDM. AFAICT, the login is so fast now that it tries to run before ConsoleKit has properly initialized! I simply added in a 0.1 second delay (because as programmers know this always fixes everything), and now it’s working perfectly again.

# Mount all USB block devices that have a filesystem label.

for device in $(find /dev/disk/by-path -name '*usb*' -exec readlink -f {} \;)
do
    if [ -b "${device}" ] && blkid "${device}" | grep -q LABEL
    then
        if ! mount | grep -q "^${device} on "
        then
            ( 
                sleep 0.1
                udisks --mount "${device}"
            ) &
        fi
    fi
done

And there we have it, a lightning fast XDM login screen, and now I can actually log out and in again as well!

Exciting hardware in 2015

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It’s been a long time since I have seen any new hardware truly excite me. The last time I can recall such an event was perhaps the release of largish affordable SSDs, or perhaps the release of high-resolution displays, which sadly are only now starting to become readily available to those of us outside of Apple’s ecosystem. Unfortunately most hardware improvements are so incremental that it’s hard to feel truly excited about something.

That all changed today, with the release of the MSI GS30 Shadow.

I’m currently the owner of an Asus G55VW Republic of Gamers i7 laptop. It’s a good mid-range “laptop”, however it’s actually a desktop replacement due to the sheer size and weight of it (and I did indeed use it to replace a mid-tower desktop – the first time I’ve ever used a laptop as my primary computer). I’ve maxed out the RAM to 32Gb, and added in a 1Tb m-SATA SSD and replaced the 1Tb mechanical SATA drive with another SSD. It also has a GTX660M which is powerful enough to run any game on the market, and thankfully doesn’t require me to deal with software to switch between the Intel integrated graphics and the Nvidia GPU – Intel graphics are not available. Unfortunately it is no longer powerful enough to run everything in the highest detail settings on recent titles as evidenced during a recent play-through of Far Cry 4. A graphics card upgrade may be in order in the near future, although that’s usually not possible on a laptop – a replacement is generally necessary. I usually use the laptop propped up on a stand with an external keyboard, HDMI-connected LCD, mouse and external Creative X-Fi 5.1 sound card.

In addition to this, I have an old Sony Vaio 11.3″ laptop with a measly AMD E-350 APU and 1366×768 resolution display. This is the laptop I use as an actual laptop – I take it everywhere with me since it’s quite light and is tough enough to take a few drops or knocks while in my bike pannier on my commute to work. Since it has some work files on it, it uses full disk encryption via LUKS. This is painfully slow on the E-350 (even with an SSD) as the APU lacks an Advanced Encryption Standard Instruction Set implementation and is a very underpowered processor in general. However it has proven tolerable for light workloads.

Interestingly the E-350 has a relatively high powered graphics processing capability. Many games such as Killing Floor actually run slower when game-play settings are set to the lowest graphics configuration due to the false assumption by the game developers that a GPU would be the bottleneck, as this option transfers more work from a GPU and onto a CPU (at the expense of graphical quality). Boosting the graphics quality up a bit shifts more work to the graphics component of the APU and results in a slight performance improvement! Ultimately, a game such as Killing Floor still runs too poorly to be playable as more enemies appear in later waves. The E-350 is best suited to simple games like the original Counter-Strike (yes, the one from 1999), and even then probably not at 1920×1080 if using an external monitor.

Since I don’t use the Sony Vaio for gaming (mostly just SSH and a basic instant messaging client), up until recently it’s worked out fine for me. It’s 100% compatible with free software drivers (although I think I may have replaced the wireless/bluetooth module at some point to avoid needing a blob), and has survived a lot of rough treatment over the years, largely due to a single fan being the only moving part. However now my workplace wishes to depend more and more on SaaS applications. I despise the direction things are heading in in this regard – where websites such as Slack, Trello and PassPack have become the norm – perhaps the subject of another post/rant. However this is the company data that is being dealt with – not my own. These proprietary SaaS applications are not being forced onto other people as is the case with traditional proprietary application vendors. It only hurts the companies which choose to use it (well, in addition to employees such as myself), so maybe I can live with it… however my computer certainly can’t. The E-350 just isn’t up to the challenge of these CPU-intensive websites.

Since I’m always on call to deal with any possible infrastructure emergencies which may arrive, I need to always have a computer with me. The E-350 was the perfect small cheap lightweight machine I could slip into my backpack or bike pannier and take with me anywhere. It is relatively fast at booting to an Xfce desktop and opening Terminator (the most time-consuming aspect is getting past the lengthy LUKS passphrase and LightDM login password). However the second I need to open Firefox to log into Slack, the browser loading times can be longer than the entire boot-up time! It’s ridiculous, especially given how PSI+ or Pidgin loads almost instantly on the same machine and provides the same functionality only with a different interface and open standards.

So now I’m in the market for a new computer. I can’t lug around my Asus G55VM as that’s too big to even fit in my bike pannier and would make my back sore if I had to carry it around in a backpack all the time. But if I’m going to get a new laptop, I’m going to want something fast, light, with a high resolution screen. It might be asking a bit much, but I was hoping to be able to use this as an opportunity to replace the G55VM as well if I could find something portable with a graphics card more powerful than an Nvidia GTX 660M (eg. perhaps a GTX 860M). This might be possible since I’d happily forego the Blu-Ray drive – I have external USB Blu-Ray drives which are faster and don’t have the firmware issues playing DVDs which the Matshita UJ160 drive (built into the Asus laptop) has.

You might be starting to get the impression I’m quite fussy with choosing a laptop, and you would be correct. In addition to the above, I also require a 1Gb ethernet port, upgradable RAM and SSD, EFI which allows manual upload of custom signing keys for Secure Boot (which I imagine means restricting my options to the three big-name Taiwanese computer manufacturers, since those are the companies that tend to market more towards people who know what they are doing and expose all possible options), a HDMI port for an external monitor (as I’m yet to see an LCD in person that uses DisplayPort), and a dedicated 3.5mm mic-in port for use with my Sennheiser PC 360 G4ME headset when I don’t have my external sound card with me.

Ideally I would also like I/O MMU virtualization (AMD-Vi or Intel VT-d) support, so I can use the laptop as a new home server when it is time to retire it from laptop use (I use Xen and would make use of PCIe pass-through to guest for the NIC in a dedicated firewall VM), a backlit keyboard, no USB 2.0 ports (everything should be USB 3.0 these days), support for a second SSD, and a matte screen. I also don’t want an Asus Transformer laptop, since I’m not interested in tablet or touch-screen functionality (which are usually glossy anyway), and I’m not confident the hinges (with the detachable keyboard) would be able to withstand much punishment.

Now, I’ve been looking for something that fits all of the above as best as I can, but everything I have found requires compromising somewhere. Maybe something comes close, but doesn’t have an Ethernet port, or is too heavy, or doesn’t have VT-d or AES CPU support. Maybe it only has a GT 840M GPU, which wouldn’t really be an upgrade over a GTX 660M. It’s almost impossible to find something in a small form factor with support for two SSD storage devices. Everything I have seen has failed to impress, so I’ve been procrastinating on making a decision about what to do.

Well, today I was browsing the PC Case Gear website, and noticed something strange in the gaming laptop section which I had not seen before. That laptop is the MSI GS30 Shadow, and it amazingly ticks all the boxes with ease due to an impressive feature. A feature so simple, I can’t believe it hasn’t been done before. In addition to being a kick-ass Ultrabook, albeit one without a dedicated GPU, it supports and includes an external enclosure which can be used to connect a real PCIe 16x graphics card to it of your choice! This external enclosure doubles as speakers (which I probably won’t use since I already have a nice 5.1 surround sound setup), a 4-port USB 3.0 hub (so I can leave my keyboard, mouse, external sound card, external optical drives, etc. permanently connected) and includes a 3.5″ SATA expansion port for an SSD to store all those games on that require a powerful GPU. The enclosure is actually a docking station which the laptop sits on top of, so I could use this to replace my existing laptop stand as well.

I’m absolutely stoked. This is almost exactly what I’ve been looking for. I’ve wanted an Ultrabook-like machine which has upgradable RAM and storage (this provides two SSDs connected via two M.2 SATA connectors), and yet is lightweight and portable and has a high-end quad core processor with IO/MMU and AES CPU extensions. But the main feature is easily having the ability to finally upgrade the graphics card in a laptop. I don’t need portable GPU power since I mainly use my laptop away from home for work purposes, but I do want it at home for personal use. And as if all this wasn’t enough, the external GPU enclosure includes an additional 1Gb ethernet NIC – perfect for re-purposing this machine as my home server in the distant future. I also wonder if I might one day find alternate uses for that PCIe slot, such as a SAS controller. It’s exciting to think about the possibilities.

Although this laptop comes close, it isn’t perfect. It seems the laptop will only support up to 16Gb of RAM. I’m used to 32Gb (mostly for when I’m experimenting with various virtual machines or using it as cache for slower external mechanical/optical drives), but I’m confident 16Gb will still be enough to not make the decrease too noticeable. I would have liked to see a QHD display resolution option, although omitting it is probably reasonable given it would only be used with the integrated Iris Pro 5200 graphics. I also have the usual complaints about Windows being forcefully bundled (and a version of Windows that I especially hate), but given how fussy I am with hardware specifications (and my dabbles with Wine which sometimes uses licensed Microsoft components), I’m not as upset about it here as other people would be. It would also be nice if the dock supported more than just one 3.5″ SSD and PCIe slot. I also wonder if other future laptops will be released by MSI that will be compatible with this dock, although that seems doubtful given the dock size doesn’t look big enough to support larger laptops.

Upon reading reviews of the GS30 Shadow, I saw references to another recently-released device with similar functionality compatible with some Alienware series of laptops – Alienware’s Graphics Amplifier (which I’ll hereafter refer to as the AGA). This is something purchased separately to the Alienware laptops it is compatible with, and has the advantage of being able to pass the external GPU graphics onto the laptop display – a feature I can’t imagine myself using – but my gut feeling is that this might complicate GNU/Linux compatibility. The Alienware solution also has some significant drawbacks:

  • The AGA connects to the laptop through a cable instead of via a dock. Although the AGA includes a PCIe 16x slot, the cable limits the bus bandwidth to PCIe 4x speeds, which will surely hinder the ability to upgrade down the road as performance will be compromised on faster graphics cards. I also feel Dell is misleading people about this as the limitation is not mentioned anywhere I could find on the website, although I can’t say I’m surprised.
  • It doesn’t include a SATA controller or mounting brackets. This is a great feature of the MSI solution in my opinion, and something I’d like to make use of.
  • It doesn’t look like something I could sit my laptop on reliably. That means I’ll have to find more desk space, and I’m not sure I would be able to comfortably find the room. I also can’t imagine cable length would be great.
  • Alienware is nowadays owned by Dell. Dell and I have a bit of history, and I’d like to avoid that company wherever possible.
  • Perhaps most importantly, there is no comparable Dell laptop compatible with the AGA – no 4th Generation i7 CPU with VT-d support in a 13″ machine, and the 13″ laptops on offer are almost twice as heavy as the MSI.

So there we go, the MSI GS30 Shadow is a winner. It isn’t actually released in Australia for another two days, but I’m convinced that the GS30 will be my next laptop sometime soon. I’ve never owned a MSI laptop before, but now I’m certainly looking forward to it.

Fun times – upgrading Xen dom0 to Wheezy

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I apologise for the downtime Sunday evening. What follows is a description of the problems I ran into which caused this.

It was about 6pm. J- and I were trying to figure out some issues we had been experiencing with XMPP. I run ejabberd in a VM on my server, which I’m reasonably happy with. J- on the other hand was using a Google Talk account, but always appeared invisible on my contact list. Yet, I was clearly visible and online on her roster.

My suspicions were that it was somehow related to Google Talk – it’s been in the news that Google is breaking federation, and they have broken it (partially at least) in the past. J- sought to fix this by signing up for a dukgo.com account. Oddly, this resulted in the same strange issue.

Next, I thought I might want to investigate my own XMPP server. I was only running stock Debian Squeeze, so figured I should probably upgrade to the latest stable before spending any significant amount of time on it. After all, how long could an upgrade take? It was 6:30pm on a Sunday evening, but I also had slides to come up with for a talk at LUV Tuesday night. Surely the upgrade wouldn’t take more than about an hour?

After all the packages had been upgraded, it was time to reboot the instance into a new kernel. That’s when I ran into my first problem – the instance refused to boot. It seemed that pygrub, which is what I was using for a boot-loader, was unable to parse the newly generated grub.cfg file.

Pygrub is a part of my dom0, which also was running Squeeze. My thinking was that hopefully if I upgraded the dom0 to Wheezy too, it will support the new Grub configuration format. Worth a shot. And so I began the dom0 upgrade.

After all the packages on the dom0 were upgraded, it was now time to reboot and cross my fingers. Thankfully, the reboot was successful. I was very glad to see the processes of runlevel 2 initiate. Very glad… except one of my instances refused to boot. Not just any instance, but my firewall! No more Internets! Panic started to settle in.

The ADSL modem connected to the server via USB. The entire USB controller was using xen-pciback for device pass-through to to the guest. This functionality was no longer working – the dom0 decided that the device was no longer available and could not be passed through. If it could not be passed through, the firewall instance refused to start (and wouldn’t be very useful even if it did). This was starting to be a real annoyance. Now I had to unload the kernel modules, play with /sys entries to free up the device, and then boot the firewall again. There was some tinkering with dom0’s Grub kernel parameters along the way, but eventually I got the firewall to boot *and* see the USB device. It took hours, but I finally did it. Sorta.

There were a ton of USB driver error messages in dmesg output of the firewall. The USB stack was failing and was unusable. I tried various pass-through configurations, but ultimately I was not able to get the guest to use any kind of USB device. Seems like some kind of regression.

At this point it was getting quite late, and I wasn’t in the mood for playing around any longer. I just wanted things working again – and preferably without having to undo all my work by restoring from backups. Fine, I thought. If I can’t pass through the USB controller, I’ll just install a spare PCIe NIC and pass through that instead. After all, my modem supports connectivity from either USB or Ethernet, and it doesn’t matter to me which.

Although this seemed like a good approach, and I had the hardware to spare, things once again didn’t work out. The dom0 kernel wanted to load the device drivers of this hardware for itself, and I would have to prevent that if I were to be able to use that in the guest. The kernel driver module was r8169. I started creating entries in /etc/modprobe.d/ and rebuilding the initramfs, which is when it hit me… this is the same kernel module as used by the other integrated network port in the server – which I very much need. If I prevent this from loading, I won’t be able to remotely connect to the server any more via my LAN!

It was somewhere in the early hours of Monday morning, I had no Internet access (except through tethering with my N900), I had to go to work the same day, I had not had much sleep the night before, I had slides for a presentation that needed to be created, and I knew J- would kill me if I left the server in this broken state for too long. Further, I wasn’t sure how to proceed, and (to add insult to injury) my N900 battery just died.

I checked the server, and observed that it had two unused PCI slots. Thankfully my home server runs on an old budget motherboard that still supported them, as I figured I could scrounge up an old PCI NIC or two. After pulling some old boxes out of storage, I did indeed find spare PCI NICs. The first one I tried required yet another r8169 kernel module, but then I found an old PCI NIC that was gigabit and had heatsinks on it! I couldn’t see what it was under the heatsinks, but given that the other chipsets were bare, it seemed it would probably be something different. Turned out to be some kind of National Semiconductor NIC. No idea where I brought it from or how long I have had it for, but it proves that sometimes it really does pay to keep old crap. :)

So, after installing it, messing around a bit with /etc/modprobe.d/ rebuilding initramfs, tinkering with the dom0 kernel parameters to provide appropriate device-specific xen-pciback parameters (because I’d forget about them if they weren’t in /proc/cmdline), changing the firewall VM configuration profile, etc… my Internets were back.

Unfortunately, even as I write this I still have not had time to go back and investigate the original issue – J- is still invisible to me in my roster when she should appear as online.

Introducing ‘usbraid’ – for efficient USB RAID management.

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Those of you who know me well also know that I’ve been doing geeky stuff for a long time, so it shouldn’t come as a surprise to learn that (while I wasn’t the first person to do so) I have been using USB RAID arrays for a few years. Unlike the linked articles however, I have generally had a practical reason for using one.

The first practical USB RAID array I ran was in RAID0 – attached with tape to the back of my Asus EeePC 701 laptop screen. The USB RAID storage was actually considerably faster than the 4Gb of internal non-upgradable flash the netbook came with.

Currently however, I use a USB RAID array to store my most confidential files on – things like my BitCoin wallet, password manager databases, important documents and the like. Why would I do that? Security and convenience, primarily. I wanted a backup solution with redundancy in case one of the drives failed, so that rules out my spare laptops which all only house a single HDD (without reaching for a soldering iron, anyway). I also don’t want to store such confidential information on my home server which is running 24×7 and always connected to the Internet – it exposes this data to unnecessary risk. No, ideally the storage device to be used for these specific backups should be only powered up when the data is actively being used.

Most USB HDDs you can buy would fail to meet the ‘redundancy’ requirement, but there are devices such as the Western Digital My Book RAID1 enclosures and the like. Unfortunately these generally house 3.5″ HDDs – overkill for the few small files I need to store securely. There are other non-apparent problems with these too:

  • The sheer bulk and weight of some of those solutions would make them very susceptible to damage if accidentally dropped.
  • They tend to rely on proprietary software and/or HDD controller chipsets which may not be easy to replace if they fail.
  • Generally, such devices are not terribly cheap.
  • In my experience, putting much trust in consumer-grade external hardware devices is just asking for trouble.

So there you have it – a very practical reason why I require a USB RAID array. Running five 1Gb sticks in RAID6, permanently duck-taped to a cheap USB hub solves all of the above problems, is silent, tougher, smaller, lighter, cheaper, more easy to replace (can just buy any other USB hub off the shelf – or in a pinch not even use a hub if a desktop has enough USB ports), and would require at least 3 drives (more than half the array in my case) to fail before losing data. As far as the hardware part of the solution goes, it’s perfect!

Of course, the software side of the story is a little more tedious. I actually run LVM to manage my partitions on top of my RAID device, so having to manually start a RAID array by specifying the device nodes of each USB key, setting the LVM volume group to ‘available’, creating mount points and then mounting each filesystem I’m interested in each time I want to use my array is actually quite a lot of work. After a bit of practice you can go from connecting the device to having the filesystems mounted in about a minute, but even that is far too long IMO – especially when you consider that you also need to do a number of steps to reverse all of this when you’re finished with the filesystems later.

A few months ago, I bit the bullet and spent a few hours writing my own solution which I now license to all (under the GPLv3): usbraid. I’ve spent most of this morning updating it to be less specific to my system and adding the included documentation, so hopefully it’s useful to somebody who might be in a similar situation. You need to know a bit about mdadm and LVM2 if you are considering making your own USB RAID setup and using this tool, but hopefully it’s not too difficult. Once setup as described in the included README file, you should just be able to simply run:

$ sudo usbraid -m
$ sudo usbraid -u

to mount and unmount your USB RAID filesystems.