Therefore, I bought three 750GB hard disks to complement the one 750GB disk that I had already. And I decided to get a bit of RAID 5 set up. I didn’t trust the fake raid card in my server box, or even believe it was supported in Ubuntu. So I had a look into software RAID. It looked pretty good, so that’s what’s setting up now.

I was a bit shocked to see the packaging Scan.co.uk sent the hard disks in, as you can see. There is also a hard drive mounting kit for a optical drive bay in there as well. Luckily, nothing seems damaged, so let’s hope it stays that way!

And this is the process I am following to get all of this organised and set up…

1. Connect up all the new hard disks
2. Format the new disks and set the RAID flag
3. Create a new blank RAID array with the three disks
4. Transfer all the old data onto the array
5. Change the /var/nas mount point to the new array
6. Format the old disk
7. Add the old disk to the array and expand the array
8. Expand the file system

It’s taking time, but it’s coming along. I’m at step #7, and it looks like it’s going to take a while. It’s at 3.9% and has an estimated time of 869 minutes left. Should give me a chance to do something useful.

Anyway… On to some revision. See ya.

More pictures?

Off I went to a Maplin store. You walk into maplin and you are instantly greeted with millions of electronic things, of which I didn’t know what they were. Walking around there, for a while, I discovered some electronic kits. These “make your own” kits are manufactured by Velleman, and I can recommend them.

So after browsing through the many different kits, I ended up choosing a Clap activated switch. Whilst I was there, I grabbed a soldering iron stand, as I already had the soldering iron + solder.

More pictures?

Opening the kit presented me with millions (ok, 20) resistors, and a bunch of other electronic parts. Two days later, and the solder sucker having to be used occasionally, the kit was finished. One thing I forgot to purchase was a transformer to plug it in with. After visiting maplin I came home and found the transformer was faulty. It is one of those changeable voltage transformers. This one, however, would only work when set to 6 volts. After getting a replacement, finding that it was faulty too, buying a different one instead, I finally got the clap switch to work.

And am I surprised that it worked first time? Well… Yes!

And where will I go from here then? Read on…

As I mentioned earlier, I’d like to get into AVR programming. Unfortunately, there is no simple kit, like the Clap switch. The parts that they mentioned I should use, in that Systm episode on AVR programming, are quite hard to find in the UK. You can go ahead and use the digi-key site that Systm recommended. One problem with that though is the postage. £15 for shipping + £5 for handling!

Eeek! After a fair bit of searching, I decided to post a forum thread. The result turned up Farnell. I haven’t found out the postage yet. But I expect it can’t be as bad as Digi-key.

Anyway…

After reading this mailing list post on ubuntu-uk, I was surprised these 3G datacards actually worked under ubuntu. Therefore, I instantly zoomed off to ebay and purchased one for £34 + postage. I made sure it said unlocked in the ebay listing, as I currently have a virgin mobile sim card and didn’t want to waste/switch to vodafone.

So the datacard turned up and I popped my phone SIM in it. Following the guide that was written in the mailing list, I configured it. This was using kppp. So I made everything was in there right and tried to connect. One problem though. Everytime I tried to connect kppp would lock up instantly. “Ah dear”, I though.

After much researching, I managed to set up the datacard using gnome-ppp, which is equally, if not more, easier to set up the datacard in. And here is a little guide I’ll write in full for you…

The guide

The vodafone 3G card. Great little thing. Get the internet almost anywhere!

Now, these vodafone cards seem to be just some re-branded ones. The real manufacture, found from the label underneath, is Novatel Wireless. The model of the datacard is Merlin U630.

Pop the SIM card into your datacard, ensuring that you put it in the right way (I may have been stupid enough to put it in the wrong way ). And then plug it into your computer. First off, it would be quite a good idea to ensure that it was detected by the system. To do this open up a terminal and enter the command dmesg. This should hopefully give you a long list of text, where the end of it slightly resembles this:

[ 124.076000] pccard: PCMCIA card inserted into slot 0
[ 124.076000] cs: memory probe 0xf8000000-0xfdffffff: excluding 0xf8000000-0xfc1fffff 0xfce00000-0xfd3fffff
[ 124.080000] pcmcia: registering new device pcmcia0.0
[ 124.080000] pcmcia: registering new device pcmcia0.1
[ 124.224000] pcmcia: request for exclusive IRQ could not be fulfilled.
[ 124.224000] pcmcia: the driver needs updating to supported shared IRQ lines.
[ 124.268000] 0.0: ttyS0 at I/O 0x3f8 (irq = 3) is a 16550A
[ 124.312000] pcmcia: request for exclusive IRQ could not be fulfilled.
[ 124.312000] pcmcia: the driver needs updating to supported shared IRQ lines.
[ 124.360000] 0.1: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A


From this you can see the ttyS0 part. This is the name the Linux has given to your datacard. This isn’t really necessary, but it could be useful to know.

Time to install gnome-ppp. Run sudo apt-get install gnome-ppp. One final thing to do in the terminal is edit a setting of ppp in linux. Run the command sudo gedit /etc/ppp/options. That will load up the text editor, so that you are able to change the options. Head to the bottom of the file and add novj to the end on a separate line. Save and close this file.

Head to Applications -> Internet -> Gnome PPP. This will load up the gnome ppp manager. Press the setup button to load up the options for connecting. Click the detect button, so that it can find your modem device, or alternatively choose the name we found earlier (in my case /dev/ttyS0). Even though it isn’t a USB modem select under type USB modem, as I found this is the setting that worked. Set the speed to 460800.

Now, you’re going to need to find your mobile provider’s APN address. I found this website had a bunch of APNs for many different mobile providers. So, as I use virginmobile, I scrolled on down to the virginmobile part and found my APN was goto.virginmobile.uk.

Pop back to the settings for gnome-ppp. Click the “Init Strings…” button. In the 3rd Init string item put the following line of code, replacing goto.virginmobile.uk with the APN for your mobile provider.

AT+CGDCONT=1,"IP","goto.virginmobile.uk"

Once you’ve entered that, press the close button in the Init Strings window. That is the end of the configuration in the Setup dialog also. So go ahead and close that too.

You’re now back to Gnome PPP main screen. If you go back to that webpage I pointed to you earlier, and down to your provider you’ll find a username and password. Copy these accross to the username and password boxes of gnome ppp. If the webpage said (leave blank) next to either the username or password, just put anything in to fill that up, as gnome ppp will not allow you to connect otherwise.

One final part is to add in the phone number to dial. This is, for most people, going to be *99***1#. Now that you’ve entered all the settings needed go ahead and click Connect. Hopefully, through the power of 3G or GPRS, you will be connected up to your mobile network and able to surf the internet.

You may have a few problems with your DNS. You’ll know this if you are not able to load a webpage like google.com normally, but you are able to via http://64.233.187.99/. In which case, I’d solve this problem by using the opendns servers. Head to System -> Administration -> Network. On the DNS tab set your DNS servers to be 208.67.222.222 and 208.67.220.220. After that, you should be able to visit sites easily again.

Now, I think that’s it. If I’ve missed anything please comment.

Bye.

And the fan failing. That was fun. It kept overheating and after much playing around, we found that the fan on the cpu heatsink had died. Shuttle being nice and kind when they designed this heatsink, made a size fan that you can’t get anywhere. Instead, I got a generic case fan and duct taped it to the heatsink! Clever, eh?

So my server. What is it serving? Well, it’s backup server. Thanks to the backuppc package, all the computers will be backed up in my house. Every week a full backup is done. Followed up by a incremental backup each day. Backuppc is also very clever. If there are files that are the same across backups and computers, the file will only be stored once. I can’t backup my whole house yet though. This is because of the hard drive in the server. It’s only a 120GB one. That means I’m currently only backing up one computer as a test.

What else is my server serving? SSH. The first thing I did when I set up the server was install SSH. This is for two reasons. The server is now on top of a shelf somewhere else in the house with only power and an ethernet cable attached. SSH is my means of remote access. The other reason is so I can have a nice SSH tunnel when I go to sixthform in September. No more annoying school filters to me Another part of my SSH server is a key based authentication. I decided that I didn’t really want to put my server out on the internet, if someone was able to bruteforce the password. Therefore, I have set up key based authentication and completely turned off Password authentication.

Quotas. I also managed to set these up. Just as a play around really. It was pretty simple to do:

1. sudo apt-get install quota
2. Open up fstab and pop in the usrquota option to the partitions that need to be quotaised
3. Restart
4. sudo edquota -u username
5. The quota config for that user will show up. Under the blocks and inodes column, you are able to see what the current use of that user is.
6. You are then able to edit the number of blocks (1,000 blocks = about 1MB) that the user can make under the first hard and soft columns.
7. The second quotaing is the number of files which can be set under the second hard and soft columns
8. Save and quit. You’re set!

What’s the difference between hard and soft quotaing you ask? From what I’ve read around the internet, a soft quota is one that limits the user slightly. The user is allowed to go over the soft quota. But only for a limited time, before they have to delete the files. The hard quota is a strict quota. You hit that quota, and that’s it. Delete the file or be able to do nothing!

And of course, to do my bit, my server is folding proteins. Slowly but surely…