Saturday, 22 December 2012

SSD Fail

Well I've learned some things about SSD drives and my old Compaq Presario.  

  1. The first hard drive to boot is the one plugged SATA port 0 and you can't override that in the BIOS
  2. Even when you get the SSD to boot it runs really slowly
  3. The  AS SSD Benchmark is a really good tool for diagnosing SSD performance issues
  4. If your SSD is running in IDE mode then it will be really slow.  To fix it you need to be able to run in AHCI mode
  5. But...the Compaq Presario has a Intel ICH7 southbridge chip set that doesn't support AHCI

So I can't use my new SSD on my old PC.  I'll have to put it into the newer Zoostorm PC.

Sunday, 16 December 2012

Failure Installing the SSD Drive

My new SSD drive arrived and I've been spending spare moments this weekend trying to install it -- without success. I've been mostly following this Lifehacker article on installing a new SSD.  Here's the steps so far...


  1. Using a combination of CCleaner and Windows Disk Cleanup I managed to get the disk usage on the old drive down to 247GB so it should just about squeeze onto the new  256GB SSD.
  2. I turned off the PC and installed the SSD in the 3.5" disk adaptor bracket.
  3. My first discovery was that I had no spare SATA power connectors.  I temporarily took the one out of the CD Drive. On Sunday I got an adapter from Maplin 
  4. I defraged the old HDD
  5. I used EaseUS to copy my C: drive onto the SSD drive.  I asked EaseUS to put 2MB unallocated at the start of the SSD as per the next step in LifeHacker.  That might have been a source of problems as the LifeHacker article suggests letting GParted do that
  6. I tried to get the SSD to boot via the BIOS.  It didn't work.  The drive complained that the disk wasn't bootable
  7. Next I tried EasyBCD to fix the boot record.  That got the SSD dual booting having started the boot on the old HDD.  If I told the BIOS to boot straight from the SSD it still said it wasn't bootable
  8. I then asked EasyBCD to fix the MBR.  I selected for it to "Install the Vista/7 Bootloader to the MBR" but the program crashed!
  9. Feeling a little desperate I bought a copy of the Windows Vista Recovery Disk from Neosmart.  I followed the instructions, let it run the auto recovery and it said it has fixed the boot data.  However, booting through the BIOS still failed
  10. I've now decided to give up and start again.  As I write this I'm defragging the HDD one more time.  I'll then start back at the top of the list of instructions and see what happens this time








Thursday, 13 December 2012

SSD Drive

My 2009 vintage Compaq Presario is running out of disk space.  I've been convinced that SSDs are the way to go.  The PC is running SATA II supporting up to 3GB/s transfer rates.  I've ordered 256GB SATA II SSD from Crucial.

In the meantime CCleaner has bought me back about 20GB of cleaned up temp and cache files.

Sunday, 9 December 2012

Spanning Backup for Google Accounts

I've just purchased Spanning Backup for our home Google Apps accounts.  I feel that I should really write a little script to pull my Google data out to a local hard drive periodically.  I've got a year to find the time to write that script before I need to renew Spanning.

Wednesday, 5 December 2012

Podcast on John Locke, Prices and Morality

I really enjoyed the Econtalk podcast on John Locke's views on economics, prices and morality.

SSH From Behind the Firewall

We've just got a network connection at the college where the boys do music.  Unfortunately the firewall blocks ssh traffic.  In order to get round this I've set up the ssh daemon to listen on port 443 and that gets round the firewall.

Here's the steps:

  1. sudo vi /etc/ssh/sshd_config
  2. Add in the line Port 443
  3. sudo /etc/init.d/sshd restart 

Tuesday, 27 November 2012

Mac to Raspberry Pi Over Ethernet Cable

Here are some really quick notes on how to connect a Raspberry PI via a ethernet cable to a Mac in order to run the PI in head-less mode over SSH from the Mac:

  1. Get the Raspberry Pi running connected to PC and monitor
  2. Plug the ethernet cable between the Pi and the Mac
  3. Set up internet sharing on Mac for the ethernet interface
  4. To find the IP of the Pi: grep OFFER /var/log/system.log
  5. ssh pi@[the IP address from the grep]

Sunday, 21 October 2012

Cross-Platform Password Manager

I've been using KeePass as my password manager for some time now.  It works on Windows and the Android, but on OS X it runs under Mono and there is a bug that means it won't paste passwords into the Mac buffer.  This makes the password manager practically useless for decent, and hence impossible to type, passwords.  I'm on the look out for a replacement password manager.  I'm going to give LassPass a try.

Saturday, 6 October 2012

Manchester Raspberry Pi Jam October 2012

We won't be able to make the Manchester Raspberry Pi Jam October 2012.  #1 son and I do still intend to work on a more powerful set of LEDs for the Morse code sender.  We might even have a chance to have a go at the receiving end.





Sunday, 30 September 2012

Diagnosing Routing Problems

A friend of mine was having trouble with web requests not working to a specific site from his home office.  The usual investigations of DNS, tracert and the like showed that the requests were heading off to the correct server, but they never seemed to return.  As my friend didn't have admin access to the server to check if the requests arrived, I decided to set up a proxy to see if that would help with the diagnosis.  Here are the steps:


  1. Installed squid using aptitude
  2. Aptitude turned on squid by default.  As I didn't want to risk having an open proxy, I turned it off with:  sudo /etc/init.d/squid stop
  3. Edited the config file: sudo vim /etc/squid/squid.conf
  4. Added access line just for my IP
    1. acl allowed src 123.456.789.012
    2. http_access allow allowed
  5. Fired up the squid server with: sudo /etc/init.d/squid restart
  6. Added the proxy settings to the browser:  my.address.com, port 3128
  7. Checked the access log: sudo less /var/log/squid/access.log
  8. That seemed to be working fine, so I remembered that there had been a really good post on the GeekUp mailing list about monitoring traffic hitting a server, so I went and had a read
  9. I installed tcpdump with aptitude, and then...
  10. sudo tcpdump -i eth0 host targetserver.com

With the proxy set up the PC connected to the target server just fine.  I think it is something wrong at the server end and I don't have control of that.  Over to the server's admins...

Sunday, 23 September 2012

NTFS Limits On Linux

I've come unstuck with my backup approach of using an external USB drive on Linux formatted with NTFS.  Duplicati puts lots of files in a single folder for a big backup.  I ran up against the limitations of ntfsmount.  The ever helpful serverfault hive mind told me I should really be using ext3.  I agreed with them.

Here's the steps to try again.
  1. umount /dev/sdb1
  2. Unplug an copy anything important over to a windows PC
  3. Plug back in
  4. mkfs.ext3 /dev/sdb1
  5. mount /dev/sdb1 /mnt/usbdrive

File Editor And SFTP Combinations

Just a quick note to list my current combinations for editing remote files over SFTP is:

Windows PC Based

Notepad++ and the NppFTP plugin that comes in the default installer.

Mac Based


Android Based

Friday, 21 September 2012

NTFS USB Drive On Debian

I'm just diving in to getting NTFS working on my Debian server.  Here are the steps so far...


  1. Use aptitude to install ntfsprogs
  2. Plugged in the USB drive
  3. Watched /var/log/syslog to see what it thinks about the USB dive
  4. The logs show that it assigned it to sdb1
  5. Created a mount point at /mnt/usbdrive
  6. Mounted with: ntfsmount /dev/sdb1 /mnt/usbdrive
  7. Hmm...the mount failed and it said I needed to chkdsk /f on windows.  I gave it a whirl
  8. Windows didn't report any problems, so I tried again
  9. Debian worked like a charm
Off to set up the mounted drive as my Duplicati backup.

Tuesday, 18 September 2012

New Backup Approach

I've decided that the time has come to move on from my current backup solution with Wuala. Now that I need about 200GB backed up I'd be looking at a bill of around £150 plus per year. The new plan is that I'll set up the backup infrastructure myself.
I'm going to use Duplicati as the software to drive the backups. I'll have an SFTP server set up on the home LAN  to which I'll configure all the local PCs to backup to each day. I then plan to setup a Raspberry Pi with an attached USB disk drive as an offsite backup. I'll install this in my father's house and get my home LAN server to again backup to it overnight using Duplicati.

Sunday, 9 September 2012

Manchester Raspberry Pi Jam

#1 son and I had a great time at the Manchester Raspberry Pi Jam at Madlab on Saturday.  We got the Pi up and running and making an LED flash morse code out.  Turns out you've got to worry about the length of the gaps just as much as the length of the flashes.

Here's a video of the Pi saying 'Hi Mum'.  I promise it is the Pi doing the work and not the laptop.

The plan for next time is to make a bright enough light source that another board connected to a Pi can read the Morse Code back in using a photo-resistor.

Wednesday, 5 September 2012

Raspberry Pi Running Headless

I've got the Raspberry Pi up and running in headless mode.

  1. I used the general instructions here: http://www.engadget.com/2012/09/04/raspberry-pi-getting-started-guide-how-to/ 
  2. With specific headless information from here: http://www.penguintutor.com/linux/raspberrypi-headless
  3. Installed the Debian Raspbian “wheezy” image on the SD card
  4. Connected power and Ethernet cable
  5. Found the IP address off the router
  6. ssh to the pi user on that IP using password of 'raspberry’
  7. Ran the setup with sudo raspi-config

Saturday, 1 September 2012

Off To Arduino Course

I'm on the tram on the way to the Arduino course at Madlab. Very excited.

Thursday, 30 August 2012

Setting Up For The Omniversity Arduino Course

I'm very excitedly setting up for the Madlab Omniversity Arduino course this weekend.  I'm following the instructions to set up the Ardunio on the Mac.  It worked like a charm.

I wonder if I have to take my soldering iron...

Tuesday, 17 April 2012

Wiki Setup For Lego League

I've set up a new MoinMoin wiki for my son's Lego League team.  Here are a few quick notes to myself about what I did for future reference:
  • Installed MoinMoin from aptitude
  • Read the installation docs from /usr/share/doc/python-moinmoin/README.Debian.gz
  • Created the directories for producing a wiki called “lego”
  • Added site to /etc/apache2/sites-available
  • Configured MoinMoin by editting /etc/moin/mywiki.py
  • Edited /etc/moin/wikilist
  • Called a2ensite to active the wiki
  • Restarted the apache server with invoke-rc.d apache2 reload
  • Went http://your.site/MyWiki/LanguageSetup to set up username and password
  • Installed the English language pack all_pages
  • Turned on apache mod_rewrite
  • a2enmod rewrite
  • Edit /etc/apache2/sites-available/lego to include
RewriteEngine on
RewriteRule ^/$ /Lego/FrontPage [R]
  • Restart apache again
  • Make so only registered users can edit:
    • Edit /etc/moin/mywiki.py
    • Add line: acl_rights_default = u'Known:read,write,delete,revert All:read'
  • Set up site uptime testing at http://pingability.com

Saturday, 14 April 2012

Getting Started With Open Wonderland

I've been looking to build a 3D environment for our home education Lego League team to hold virtual meetings.  After a couple of false starts I'm working my way towards a functioning Open Wonderland server.

The Basic Setup


I've got an old laptop running a headless Debian installation.  I've put the Sun/Oracle JRE on the server.  For then it was a very straightforward job to download the jar file and fire it up.  It took a while on the slow old laptop for the server to get itself started, but once it was ready it politely told me the URL to connect to.  Over to the client PC and the server's URL took me to a page to down load a Java JNLP file from which the client sprung into life.  I soon had an avatar going and was merrily walking around the Open Wonderland world.

Audio Problems

The main set up problem I had was that I couldn't get the Audio to work from the server.  A little bit of tweaking with the Windows Control Panel got the client audio going, but I couldn't get anything back from the server.  I headed over to the Open Wonderland community pages to find some help.  My first port of call was the IRC channel.   There was no sign of life there, so I next tried the Google Group. There was at least some discussion taking place on the group.  I posted a "please help the newbie" message and left it for the evening.  The next  day I had had no response from the group, so I dived into trying to figure out the problem myself.  Locating the log files was less than obvious.  The root of the log file directory was in .wonderland-server below the home directory of the user that I had used to run the server.  Digging into the ~/.wonderland-server/0.5/log directory I found the voice_bridge.log file.   Delving through the log file I spotted that the "Bridge private address" was set to 127.0.0.1.  I figured that would mean none of the server audio traffic would be being routed between client and server.  A small amount of digging into the server's /etc/hosts file found the name of the server being mapped to 127.0.0.1.  I tweaked that to the IP address of the ethernet card, restarted everything and hey presto the audio worked.

I've since had three clients with audio running simultaneously on the home LAN.  Next job is to set up the server on the public internet and see what the performance is like with remote users.




Tuesday, 27 March 2012

Minecraft Running On Old Laptop

I've been setting up the Minecraft client on an old Dell Inspiron 1300 laptop running Windows XP. The basic installed failed complaining that I had a bad video card driver. The solution was to go into Control Panel, click Display, pick Settings, Advanced. Under that menu find Troubleshoot and turn down the hardware acceleration settings. Mine worked at just less than halfway turned on. In order to get the client to run without too much lag I had turn turn the render distance down and turn off other fancy graphics options.

Sunday, 5 February 2012

Which Bookmarking Tool To Use

I'm between bookmarking tools at the moment. I've been happy with StumbleUpon for a while, but I've just given up on their new UI. It requires you to remember too much mystery meat to get anything done. I had used Delicious before that. I can't really remember why I stopped using it. I think I liked the old StumbleUpon more. I'm considering using Google's +1 facility, but again that seems a little obscure.

Here are my requirements:

  • Save bookmarks
  • Work quickly from Chrome or Firefox
  • Work okay from the Android browser on a phone
  • Support tags
  • Able to be viewed as a web page rather than tied to a browser (rules out Firefox Sync)
  • Easy way to get my data out again

Suggestions?

Sunday, 29 January 2012

"Family Math" - Great Book Of Maths Games

I've just finished reading Family Math. This is a book of games and puzzles focused on giving kids interesting challenges while stimulating mathematical thinking. A couple of favourites have been about an algorithm for palindrome numbers (try 89) and "Ten Card Arrangement" where cards are dealt and shuffled in a repeatable way and you have to stack the deck to come out correctly.

Highly recommended.

We've just done the RSPB Big Garden Bird Watch 2012. Here's what we found:
BirdMax Number
Blackbird2
Magpie2
Carrion crow1
Woodpigeon3
Coal tit1
Blue tit3
Nuthatch2
Jackdaw1
Song thrush1
Robin1
Chaffinch1
Great tit2
Wren1

Saturday, 28 January 2012

Security Scan

This is just a quick list of things I'm going to do periodically to test the security of the systems I'm running:

  1. GRC's Sheilds Up utility on all external network interfaces for machines that I can run Chrome on
  2. On the server I have no GUI and Shields Up doesn't run in Lynx. Instead I used nmap

First time through with Shields Up I found that my home router had the SNMP port 161 open. This is a BT Home Hub version 3.0. It would appear that it is not possible to turn this off. I'll have to raise a help request with BT to turn it off.

On the server I had a surprise that ports 554 and 7070 were open. Looking in /etc/services it said that 554 was Real Time Streaming Protocol, and 7070 wasn't listed. To find out what was listening on the ports I ran:

sudo lsof -i :554
sudo lsof -i :7070

Both of those returned nothing. Next I tried:

sudo netstat -a |grep LISTEN |grep -v unix

That didn't find anything bound to those ports at all. I asked the helpful people at Rimu Hosting if they knew what was going on.

Update 29 Jan 2012: The Rimu Hosting people came back and said that when they ran nmap against the IP address they didn't see anything on ports 554 or 7070. Strange. I need to get someone else to run the nmap scan from a different location to see what they see.