Cant find any wireless networks

gomer

Hmmm ... I've always had luck with the madwifi driver for the atheros chipsets. Try this:

sudo rmmod ath_pci
sudo modprobe ath5k

sudo iwlist scan


See if that gives you any more luck.

I also may have asked this already, but what version of Ubuntu are you running, and version of the kernel ? ( uname -r )

David1729

david@david-laptop:~$ sudo rmmod ath_pci
[sudo] password for david: 
david@david-laptop:~$ sudo modprobe ath5k
FATAL: Module ath5k not found.
david@david-laptop:~$ sudo iwlist scan
lo        Interface doesn't support scanning.

eth0      Interface doesn't support scanning.

david@david-laptop:~$ uname -r
2.6.24-28-generic

I believe it's Hardy Heron (8.04).

gomer

Would you be willing to consider upgrading to a more recent version? I'm assuming you stuck w/ Hardy all this time because it was an LTS release. Ludic is an LTS release, too, and ships with a more modern version of the kernel, and better hardware support. You may find that the upgrade may fix your problem. If you're afraid that Lucid will look too different, might I also suggest that you consider Karmic, as it still has that Ubuntu "human" theme w/ the Orange and brown that you are probably comfortable with. I'm pretty sure that your hardware will work in Karmic, too

David1729

"stuck w/ Hardy"? I didn't see any reason to change. Are you implying that I was supposed to upgrade every time they released a new version?

gomer

Not necessarily. There's no reason to upgrade, I guess, if everything works fine for you. But clearly, that's not the case.

You're running Kernel 2.6.24, which still relied on madwifi to run the Atheros chipset. That also means that some of the code that runs the software dirven radio in those cards is closed source. Drivers that require cutting a binary from the chip, the downloading of closed source firmware and plugging into the kernel have a lousy track record.

In 2.6.25, the ath5k driver was included in the kernel, which is a completely FOSS driver native to the kernel for the Atheros chipset.

If you absolutely want / need to stick with Hardy, then you may end up needing to patch the madwifi source and re-compiling and re-installing it. Or, you may need to consider rolling your kernel / kpkg to get to the ath5k driver. But frankly, I tihnk in your case upgrading Ubuntu is going to be much easier.

David1729

OK, I wasn't sure how to verify the download, so instead of a clean install I just upgraded to Lucid. WiFi and sound now work, but the screen size is still wrong and some other things haven't gone smoothly either. So I'd like to do a clean install. This begs some questions: How do I check that I've downloaded the iso file correctly? (I.e. how do I check the checksum and where does it say what the checksum should be?) How do I check that it's burned on the CD correctly? And how do I uninstall the current installation?

gomer

There's really no need to uninstall. you can install right over the current installation, and just be sure to chose to format the drive during the install process.

It's funny that the MD5 sums are not on the site. Interesting. None-the-less you can get the sums from one of the mirrors. For example, look here: http://mirrors.rit.edu/ubuntu-releases/10.04/

To check the sum, after the download, pick whether you want to do an md5sum or a sha1sum. They have both posted on the mirrors. Then on the CLI, it's as simple as "mdsum <file>" or "sha1sum <file>". Then compare the the value it outputs with the value form the mirror to make sure it's a match.

Frankly, I'm not sure how you would check the burn. Maybe someone else has some advice for that?

jabirali

How do I check that I've downloaded the iso file correctly?

Download this file to the same directory as the .iso file, and open Applications -> Accessories -> Terminal. Assuming that the .iso file and the MD5SUMS file is saved on your desktop, enter these commands in the terminal:

cd $HOME/Desktop
md5sum -c MD5SUMS | grep OK

If your file is not corrupt, that command should return something like this:

ubuntu-10.04-desktop-i386.iso: OK

How do I check that it's burned on the CD correctly?

Many CD burning applications will allow you to check whether or not the disk was burned correctly. I'm not sure if Brasero, the default burning application in Ubuntu, supports this though. If not, there is also an option in the boot menu of the Ubuntu installation disk to check the integrity of the disk.

And how do I uninstall the current installation?

You don't. You backup your important data, and format/overwrite the existing Ubuntu partition. If you haven't already, I suggest creating a separate partition for /home to make future system upgrades/reinstalls smoother (since your personal data won't be lost during a reinstall as long as you don't reformat the /home partition).

David1729

OK, that didn't work so well...

I still couldn't work out how to check that the CD was burned properly, but I burned it anyway. Maybe I should try doing another copy.

One hardware question: Is it OK to label the CD using a permanent marker? (I don't mean on the side where the laser beam is.) I've always thought it was, but maybe not.

Goineasy9

I use markers on my CD/DVD's without having a problem. Small words on the outer edge.

mfillpot

In some cases the iso's don't have MD5SUM files to download with them, in those cases you need the MD5SUM key from the website that directed you to the download. In your cas you can find the appropriate md5sum for your iso in the left column of http://mirrors.rit.edu/ubuntu-releases/10.04/MD5SUMS next to the iso name.

You can verify it by running "md5sum IsoFile.iso" (replace isofile.iso with your iso name) then compare the resulting sum against the one output by md5sum. In my case I usually only verify the last 6 characters by eye since the string is quite long.

As for writing on the disks, a permanent felt tip marker is acceptable for writing on the disks, unless you press really hard it should not effect the foil.

David1729

The iso file is intact. (And I downloaded it on Windows and checked the checksum on Linux, so it doesn't look like a character mapping problem.) But someone said something about checking whether the file had burned to the DVD correctly. This was the bit I couldn't work out how to do.

Someone said I could run a check from the CD's boot menu. But I can't find the boot menu. I don't even know what the filename extension for batch files in Linux is. It said that running from boot doesn't work on my computer, and offered the option (which I accepted) of modifying the hard disk's boot sector so that there's a menu at startup where I choose between Windows and Ubuntu-from-CD. Anyway, the upshot is if someone can help me find the boot file then maybe I can run it (or part of it) to check the integrity of the CD.

The file was ubuntu-10.04-desktop-i386.iso . How do I know if this is the right file? How badly would I expect it to go wrong if I got the wrong iso file? At the moment, Linux sort of works, it's lost most of the previous bugs but picked up some new ones, and it crashes quite a lot.