Is Google Hypocritical for dropping H.264 but not Flash

January 12th, 2011 by Alex 2 comments »

This blog post is a response to a post by John Gruber.

The argument is that Google are hypocritical for not dropping support for Flash at the same time as supporting WebM instead of H.264.

In my view, saying this is hypocritical is complete rubbish.

Whatever your opinion of Flash, it’s widely used on the net at the moment and has some features that cannot be replicated SENSIBLY by HTML5 at the moment. In time that will change, but that’s the reality of the situation at the moment.

Chief amongst those features is access to client side audio and video from webcams. Flash is the only sensible way of accessing these resources and streaming them beyond installing additional plugins (which may or may not be any better than Flash’s effort).

In WebM, Google has a patent free alternative to H.264 (the Apple-preferred codec which may at any time cease to be free for use on websites). The quality of WebM encoded video is arguably very slightly lower than H.264, but immaterial when discussing low bandwidth streaming in a browser. Google’s commitment to integrating open standards understandably sees them implementing WebM in Youtube and Chrome because it’s a sensible and viable alternative to H.264. Sure, right now there’s no hardware acceleration for decoding WebM, but that will come in time. Of the major browsers, Microsoft Internet Explorer, Opera, Firefox and Chrome will all support WebM/VP8 encoded video in HTML5.

There is currently no credible alternative to Flash. If Google were to abandon Flash purely on the basis that it is propitiatory,  they would be cutting off their own nose to spite their face. In the same way that H.264 served them until there was a viable alternative (in WebM/VP8), Flash will continue to serve Chrome users until the shortcomings in HTML5 are addressed.

If, and only if, at that time, Google choose not to remove Flash in favour of the open standard, then they can justifiably be called hypocrites.

2 comments »

Posted in Android, Computing

FileHunter 0.4

November 10th, 2010 by Alex 1 comment »

One small bug fix to FileHunter today:

  • Ignore symbolic links when searching the haystack

FileHunter-0.4.tar.gz

1 comment »

Posted in Uncategorized

Hell Freezes over – Is Steve Jobs right?

October 25th, 2010 by Alex No comments »

It’s been widely reported that Steve Jobs thinks that 7″ tablets from RIM and Samsung are “dead on arrival”. The 7″ screen isn’t big enough for a pleasant touch screen experience and in any case they’re too expensive.

I seldom find myself agreeing with Steve Jobs, but I think he might just have a point here.

Today by “IT Buyers Guide” from BT Business Direct dropped in to my pigeon hole and their quoting £509.79 plus VAT for the Samsung Galaxy Tab – that’s a penny short of £600 for a tablet PC. I don’t see how that is a sensible price for a tablet in anyone’s book.

I’m toying with getting a couple of tablets for my staff to use when they’re out and about in classrooms to cut the amount of walking back to the office needed to pick up new jobs – but at £510 each there’s no way I’ll be buying Galaxy Tabs.

Equally I won’t be buying iPads, lovely as the hardware is, because of Apple’s attitude towards app developers and the devices’ junkie-like iTunes habit.

Is 7 inches enough?

Quite frankly I don’t think so – especially if the screen in question is a 16:9 or 16:10 aspect ratio. Tablets look like they should be used in the portrait orientation, as you would a clipboard, yet with a 7″ screen that forces web content to be relatively small. Those extra 3″ coupled with a 4:3 aspect ratio makes a huge difference.

I guess time will tell if Samsung has found a form factor that people like using. Having used a Dell Streak briefly it felt like a large phone (which it essentially is) and I see the Galaxy Tab as a slightly enlarged version of that – although at 7″ you’re going to look alot like Dom Joly using it!

Personally I want a 10″ device, powered by Android or maybe even ChromeOS and I’m hoping that the muted Google Tablet will be very much along those lines.

No comments »

Posted in Android, Computing, F1, Linux, Open Source Schools

Direct Email to Schools – Why SchoolEmails.com are scum

July 7th, 2010 by Alex 2 comments »

It’s a fact of life that if you work in Education ICT once someone gets hold of your email address then it’s very hard to turn back the tide of unsolicited “opt-in” email lists that you find yourself subscribed to.

Generally it’s a case of clicking through an unsubscribe process for that company and you don’t hear from them again.

Not so with customers of School Emails. School Emails aka SchoolsRegister seem to be a particularly obnoxious company in the way that they deal with the email addresses they claim you have given them for inclusion in their listing.

In my dealings with them I have requested on 3 separate occasions via email and twice via their web form to be removed from their lists – yet I’m still bombarded by emails from their customers over a month on. They also refuse to tell me how they obtained my contact details and what opportunities I was given to opt-in or out of their service and on what dates.

Of particular note for being ignorant and unhelpful are PromoPrintUK aka Money4school.co.uk who initially sent all their mailings with no unsubscription information, and then tried to tell me they have no control over who they send their bulk emailings to.

Their later mailings do finally carry unsubscription information, however it’s just a link back to SchoolEmails web form which we already know is studiously ignored by the company.

Other companies I’ve encountered using their services include WTA Education Services who are at least helpful in removing email addresses from their bulk mailings.

If you’re a company considering bulk-emailing schools, think long and hard before subjecting your potential customers to emails via SchoolEmails. They clearly don’t care – do you want your company to be associated with that attitude?

2 comments »

Posted in Computing, General

Open Letter to Simon Kirby

May 12th, 2010 by Alex 3 comments »

The upshot of the General Election for me was a change in Parliamentary representative in the form of the Conservative MP Simon Kirby.

There follows an open letter to Mr Kirby outlining my suggestions for cuts to the BSF program which would potentially save the country millions of pounds and safeguard jobs in to the bargain. I also mention the need to repeal or heavily rework the Digital Economy Act and to urgently look at Copyright reform.

I intend to publish here any response I might receive.

Dear Mr Kirby

Firstly my congratulations on your recent election success, and your parties subsequent proposed coalition Government with the Liberal Democrats.

As my elected representative, I’m taking a couple of minutes to put to you my point of view on a couple of important issues in the hope that you can take my views on board.

One of the stated aims of the Conservative Party is to begin cutting the budget deficit with immediate effect. May I suggest a thorough review of the Building Schools for the Future scheme and the quango appointed to run it (Partnerships for Schools) would be an excellent point to begin.

BSF in its conception was a revolutionary rework of state-funded secondary schools nationwide, however over time it has become clear that the needs of large businesses have been pushed to the fore and it is now the normal situation in a BSF scheme to spend millions of pounds unnecessarily on consultants, propitiatory software and replacing nearly new equipment like-for-like at each and every school it touches.

Education desperately needs its funding for ICT, but schools that have invested in their ICT services are being penalised by this levelling process that has been imposed by Partnerships for Schools.

Supporters of the BSF program would say that it’s possible for schools to opt out of the Managed ICT Service side of BSF – and it is, theoretically and on paper. In reality it’s a very long and difficult process to demonstrate that existing provision exceeds that offered by an MSP. It falls to the school – which is rightly working towards educating its students – to counter the claims made by dedicated teams from the MSPs. It’s not surprising that almost all schools that embark on that route fail to win their argument.

Please therefore consider cutting the monies spent on the BSF Managed ICT Service such that the remaining funds are spent directly where they are needed by frontline ICT staff, Headteachers and Governors in schools rather than wasted on consultants and replacing systems like-for-like.

The previous Parliament also presided over the farce that was the passing of the Digital Economy Act. The arguments surrounding that act are well publicised and I’m sure you’re aware of the pertainant points.

Nick Clegg made an election promise to repeal the Digital Economy Act if the Liberal Democrats were in power. I hope that the Con-Lib coalition will seriously consider repealing the act or at the very least undertake a major overhaul of the act to address the very serious shortcomings that it has.

And finally please use this period of Conservative-Liberal accord to tackle the issue of Copyright reform. The UK is still applying copyright laws passed decades ago to modern business practises and I’m afraid they just aren’t fit for purpose any longer. Indeed proper copyright reforms would largely address the contentious issues that the Digital Economy Act attempts to legislate around and would probably negate the need for its existence at all.

Yours sincerely

Alex Harrington

3 comments »

Posted in BSF, Computing, Linux, Open Source Schools, Politics

Tags:

Xibo and MythTV

April 14th, 2010 by Alex 2 comments »

W’e've got a new room at work for our older students which has a TV mounted on the wall for Digital Signage.

What we wanted to do was provide a live/recorded TV function for breaks and lunchtime and then an easy way to switch over to our Digital Signage solution (Xibo) at other times.

It turned out to be reasonably simple.

First we installed and configured a new MythBuntu frontend (we already had the myth backend server running from a different project). I then installed the Xibo Python client (1.1.0a21) and made a small modification to the code to allow it to exit by remote control button press (our Media Centre remote sends a backspace character when you press the back button):

if e.scancode == 22:
    log.flush()
    self.parent.downloader.running = False
    self.parent.downloader.collect()
    self.parent.scheduler.running = False
    self.parent.scheduler.collect()

    log.log(5,"info",_("Blocking waiting for Scheduler"))
    self.parent.scheduler.join()
    log.log(5,"info",_("Blocking waiting for DownloadManager"))
    self.parent.downloader.join()
    log.log(5,"info",_("Blocking waiting for Player"))
    self.player.stop()
    os._exit(0)

That block was added after line 2852 appropriately indented of course :D

It’s then a simple enough job to add a Xibo button to the MythTV menu.

As your mythfrontend user (ie the user that automatically logs in to Mythbuntu on boot), do the following:

mkdir ~/.mythtv
cp /usr/share/mythtv/themes/defaultmenu/mainmenu.xml ~/.mythtv

You then edit ~/.mythtv/mainmenu.xml and add in a block like this:

<button>
    <type>SETTINGS_VIDEO</type>
    <text>Xibo Digital Signage</text>
    <action>EXEC /opt/xibo/pyclient/client/python/run.sh</action>
</button>

Then restart mythfrontend. You should have a new icon on the menu system that launches Xibo. Once Xibo is running, the client should quit when you press the back button on your remote control and drop you back in to MythTV.

Here’s a short video to show the system in action!

2 comments »

Posted in Computing, Linux, Open Source Schools, Xibo

Tags:

Backup KVM Virtual Machines on OCFS2 Filesystems on an OpenFiler SAN Appliance

April 13th, 2010 by Alex 2 comments »

We’re using a large OCFS2 partition shared across multiple hosts to provide shared storage for our KVM virtual machines.  We chose OCFS2 because it has a relatively easy setup when compared to GFS (especially since we use Ubuntu as the host OS). The main drawback however is you can’t mount a snapshot of an OCFS2 volume on the same host as the machine that has the live filesystem mounted.

For a long time now we’ve been backing up our OpenFiler-based SAN by taking snapshots using the OpenFiler web interface, and then on a separate machine using a combination of dd and ssh to take a block-level image of the SAN and archive it off for possible disaster recovery.

It works quite well but restoring anything from that image is a total pain. I compress the image using gzip too so firstly I have to find enough disk space on a different machine to extract the archive and then a significant amount of hassle to get OCFS2 setup on a standalone PC and to mount the file image. It follows then that recovering one VM from the image can take days to complete – which isn’t very satisfactory.

Another option would be to share the snapshot devices on the SAN as a new target and then mount them remotely on a server outside the cluster. That’s ideal, except that when you modify iSCSI targets or luns on OpenFiler it reloads the ietd daemon which has a nasty habit of causing the two Ubuntu hosts to stop seeing the target and taking the disk offline.

After some work I discovered you can manually tell iet to start sharing a new target or lun from the command line without needing to restart the service.

Here then is the command history I used:

  1. Take a manual snapshot on OpenFiler (I called it “backup”)
  2. From the command line on the OpenFiler appliance, add a new iSCSI target: ietadm –op new –tid=0 –params Name=iqn.2008-05.com.example:backup
  3. Find the target ID for the new target we just created. There’s a list in the /proc/net/iet/volume file. In my case I got tid:3
  4. Add the snapshot to the target. I’m using blockio with my iscsi targets. The default is fileio:  ietadm –op new –tid=3 –lun=0 –params Type=blockio,Path=/dev/vm/of.snapshot.vm1.backup
  5. Check the volume file again. You should see the export complete with the path to the snapshot.
  6. Connect to, mount and backup the snapshot filesystem using a different PC.
  7. Unmount the filesystem and disconnect from the iSCSI target
  8. Remove the lun: ietadm –op delete –tid=3 –lun=0
  9. Remove the target: ietadm –op delete –tid=3
  10. Remove the snapsh

You can now connect to the iSCSI target from a remote machine, mount the OCFS2 filesystem as needed and backup the files from the filesystem. There’s no guarantee that the images will be consistent but my experience is the machines normally come up fine after an fsck. Any lost data can be restored from the nightly backups of the machines that we take using BackupPC.

My next move is to script all this so that the OpenFiler appliance can kick off a full backup on a schedule.

Update

Here’s the finished script:

#!/bin/bash

# Create a snapshot
echo Creating Backup Snapshot
lvcreate -L100000M -s -n backup /dev/vm/vm1

# Export the snapshot
echo Exporting Snapshot over iSCSI
ietadm –op new –tid=3 –params Name=iqn.2008-05.com.example:backup
ietadm –op new –tid=3 –lun=0 –params Type=blockio,Path=/dev/vm/backup

# Sleep a few seconds to make sure iet is sharing the device
sleep 2

# Connect to nas-backup and connect to the share
echo Connecting to iSCSI target
ssh root@backup iscsiadm -m discovery -t sendtargets -p 192.168.0.10
ssh root@backup iscsiadm -m node –targetname iqn.2008-05.com.example:backup –portal 192.168.0.10:3260 –login
sleep 30

# Mount the share
echo Mounting filesystem
ssh root@backup mount /dev/sde1 /mnt/vm

# Backup
echo Backup Starting
read -p “Press a key when your backup is complete!”

# Unmount the share
echo Unmounting filesystem
ssh root@backup umount /mnt/vm
sleep 2

# Disconnect
echo Disconnecting from iSCSI share
ssh root@nas-backup iscsiadm -m node –targetname iqn.2008-05.com.example:backup –portal 192.168.0.10 –logout
sleep 10

# Remove the iscsi lun and target
echo Removing iSCSI share
ietadm –op delete –tid=3 –lun=0
ietadm –op delete –tid=3

# Remove the snapshot
echo Removing Snapshot
lvremove -f /dev/vm/backup

# Finished

2 comments »

Posted in Computing, Linux

Tags:

Microsoft Browser Choice Update – WSUS

March 15th, 2010 by Alex 7 comments »

I got bored waiting for KB976002 to show up in my WSUS install so after a little googling I discovered you can manually sync it in to WSUS.

On the front page of the WSUS console under resources there’s a link to “Microsoft Update Catalog”. If you click through that you’ll be asked to install an ActivX control at which point you can search Microsoft Update for KB976002 and manually sync it on to your WSUS install.

Once it’s synced over, you can then manually approve or decline it as you wish.

Apparently it won’t be showing in WSUS automatically until April.

7 comments »

Posted in Uncategorized

Copying a file to multiple destinations

March 10th, 2010 by Alex No comments »

Today we needed to copy a file to a whole bunch of users home folders, and fix the permissions after copying.

Here’s what I came up with:

ls -A | xargs -n 1 -IUSERNAME cp source_file.txt ~USERNAME/eportfolio
ls -A | xargs -n 1 -IUSERNAME chown USERNAME.staff ~USERNAME/eportfolio/source_file.txt
ls -A | xargs -n 1 -IUSERNAME chmod 664 ~USERNAME/eportfolio/source_file.txt

The cwd was the directory containing the home directories for the users I wanted to copy the file to.

No comments »

Posted in Uncategorized

Declining the Microsoft Browser Choice Update

March 1st, 2010 by Alex No comments »

1st of March brings the “Browser Choice” screen to all XP SP2 or later users via Windows Update, or in my works case via WSUS.

If you don’t want your users to be presented with a choice of browsers to run, (because either they don’t have permission to install software or because you already give your users a choice of browsers – as we do) then there’s a couple of options:

  • Decline update KB976002 in WSUS (you might want to set your WSUS server not to auto-approve updates until you’ve seen it arrive and have declined it).
  • Add a registry key to disable showing the balance screen after the update installs.

The update hasn’t appeared on our WSUS server yet – in fact I can’t find anyone on the Edugeek forums who have sucessfully located the update in WSUS yet.

No comments »

Posted in Uncategorized