Thread: Linux help needed - make fun of the N00b

Thanks for the pointers! I usually log in as root, but that's because I don't have a good handle on how to create a user ID.

I've ordered about 5 books on Ubuntu Linux, php, perl and SQL to get me oriented on how to do stuff right. For example, I installed proFTPd so I could put files on the plug but I've done something wrong and it doesn't recognize the command ftp: These books will help me to understand the file structure, how to add modules and make packages and so forth.

Aside from just trying to figure out the structure of the new (to me) OS, I'm going to concentrate on getting the following things working:

1. Apache web server (already installed, but need to ensure it is configured properly)
2. PHP server (again, already installed, but need to ensure proper configuration)
3. mySQL server (installed, same issue as above)
4. FTP server (ditto)
5. Add a wireless USB dongle - will need to locate and install packages
6. Take chunkyks OBDII Linux interface, recompile it for the Sheeva, see if it works
7. Write Perl script to access the OBDII data and relay it to a web page
8. Write javascript web page that displays something simple like RPM and MPH
9. Try to access that from the iPhone
10. Do the same as 6-10 using Kev000's Fusion Brain module.

That ought to keep me busy for awhile!

Originally Posted by Bugbyte

Thanks for the pointers! I usually log in as root, but that's because I don't have a good handle on how to create a user ID.

Ok, do this as root to create the user

# adduser bugbyte

You will be prrompted to enter a password twice. The other prompts you can supply info or just hit enter if you don't want to enter them until the end where you want to press 'y'.

Now to give that user sudo rights, run

# visudo

This is a wrapper script to avoid multiple people editing the sudo config file (/etc/sudoers) at the same time. As such you will be in the editor vi. If you prefer some other editor like joe, you can run

# EDITOR=joe visudo

But for vi here is how you can add a line to give the user bugbyte full root access when needed

1. use the arrow keys to scroll down to the line that looks like

root ALL=(ALL) ALL

2. Change it to be

root,bugbyte ALL=(ALL) ALL

In vi you want to get your cursor after the t in root and press 'i' to get into insert mode, type ',bugbyte', then hit escape to get out of edit mode and then type ':wq' to save and quit.

You can now ssh in as bugbyte and prefix commands with sudo, or to become root run

$ sudo su -

Originally Posted by Bugbyte

I've ordered about 5 books on Ubuntu Linux, php, perl and SQL to get me oriented on how to do stuff right. For example, I installed proFTPd so I could put files on the plug but I've done something wrong and it doesn't recognize the command ftp: These books will help me to understand the file structure, how to add modules and make packages and so forth.

Aside from just trying to figure out the structure of the new (to me) OS, I'm going to concentrate on getting the following things working:

1. Apache web server (already installed, but need to ensure it is configured properly)
2. PHP server (again, already installed, but need to ensure proper configuration)
3. mySQL server (installed, same issue as above)
4. FTP server (ditto)
5. Add a wireless USB dongle - will need to locate and install packages
6. Take chunkyks OBDII Linux interface, recompile it for the Sheeva, see if it works
7. Write Perl script to access the OBDII data and relay it to a web page
8. Write javascript web page that displays something simple like RPM and MPH
9. Try to access that from the iPhone
10. Do the same as 6-10 using Kev000's Fusion Brain module.

That ought to keep me busy for awhile!

Yeah that's a nice size list. I'm less familiar with debian based systems than rpm based systems and have not used 9.04 yet or Id just rattle of the first 4 for you. They should be easy in any event.

5 shouldn't be too big of a deal but will probably require you to learn as much as the other

8 should be easy and you can gets lots of help with that.

For the others I can't comment although I plan on doing #10 myself. Although I will say the vehicles I want to have a carputer in either have no ecu or are OBDI and one idea I had is to take whatever data collection I have and present it in a way that is compatible with OBDII output so I could leverage existing efforts for OBDII monitoring on the display side.

BTW, are you sure you need that eeprom_93cx6 module? I don't have it on my system either, but both USB wi-fi adapters I listed in my previous post work fine. At least one of them uses the rtl8187 module, too.

Edit: Never mind, I do have it. I was looking on the wrong machine. Too many linux machines.

-- Kevin

He's probably not sure. Keeping in mind he's a newbie we should explain how to discover these sorts of things.

One thing you want to get used to is watching /var/log/messages for info (same stuff that dmesg outputs goes here). The easiest is to keep multiple ssh sessions open and in one of them run

sudo tail -f /var/log/messages

tail shows the end of a file and with the -f flag it will sit there and keep reading from it, showing you stuff as it gets added in (near) realtime

With tail running, plug in a usb device and watch the log. You'll see if it recognizes it or not. Same when you pull it out you should see messages as it cleans up. Start there and see what you get.

For general usb info try 'lsusb' and 'lsusb -v'

To see modules loaded uses 'lsmod'

hth
charles

Originally Posted by cgalpin

He's probably not sure. Keeping in mind he's a newbie we should explain how to discover these sorts of things.

Right, I'm not *certain* but I got that information from the plug computing site on a thread about adding a wireless USB dongle to the Sheeva, so at least for the model they mentioned, that was what was needed.

I appreciate the help, everyone.

You mentioned proFTPD a few posts earlier. Anything that is a server, and popular, is usually easy to figure out check out this guide: http://www.ubuntugeek.com/settingup-...h-proftpd.html

I believe that after installing the ftp server, restarting is the easiest way for a noob to get it running.

Originally Posted by Bugbyte

Right, I'm not *certain* but I got that information from the plug computing site on a thread about adding a wireless USB dongle to the Sheeva, so at least for the model they mentioned, that was what was needed.

Yes it will depend on the chipset of your dongle. Try what you have and if it doesn't work, we can help figure out what chipset it is and what modules you'd need.

I needed to install jaunty on my little Fujitsu stylistic LT C500 since I am running gutsy which is now not supported, so figured I'd help you with some of your tasks now that I have at least the same version to play with. It's quite possible you won't have all the same packages available, and I have no disk space limitations to speak of whereas I suspect you will, but here is what you can do to install and test #s 1-4

#1-3 Linux Apache Mysql Php stack (LAMP)

I know you have apache, php, and mysql already installed, but if you have any trouble or just want to be sure, you can do it the lazy man's way with

sudo tasksel install lamp-server

Then you want to confirm it's working. We can test all 3 in one fell swoop with something that you might also mind useful in the future - phpmyadmin. So install it with

sudo apt-get install phpmyadmin

It will prompt you for your root mysql password, and then setup a phpmysqladmin user and prompt you for a password for that. Everything else is taken care of for you and you can run it by going to

http://PLUGIP/phpmyadmin

The login is phpmyadmin/passyougaveduringtheinstall

You can of course go old-school and make your own test page under /var/www. Assuming you are doing this as root (for permissions), run

echo "<?php phpinfo() ?>" > /var/www/phpinfo.php

And then you can hit the page at

http://PLUGIP/phpinfo.php

#4 proftpd

I assume you chose standalone when prompted during the server install, but in your case inetd would actually be lower resource use imo. But I think ftp is a dead protocol anyway, so I won't digress

Verify it's in standalone mode with

grep ServerType /etc/proftpd/proftpd.conf

You should get back

ServerType standalone

Start proftpd with

sudo /etc/init.d/proftpd start

You can now ftp to the server (not as root by default). You can test locally with

ftp localhost

And login as your non root user. Or from any other machine on the network. By default you can access your own home directory, but you'd need to do some configuration to allow access to other directories. If for some reason it doesn't auto start after a reboot, run

update-rc.d proftpd defaults

And it should start automatically on subsequent reboots.

I'd personally transfer files over ssh (see fugu on a mac, or winscp on windows). You can even setup passwordless keys and make it super easy.

hth
charles

My Fusion Brain arrived yesterday so I can give you a head start on #10

Kev's dbus daemon comes with a copy of FB so you just need to download it. I'm sure it will be hosted somewhere at some point but for now you can dig it up from this thread here:

Fusion Brain program for Linux

http://www.mp3car.com/vbulletin/atta...nux-fbd.tar.gz

First you'll need to install some dependencies (again this is on x86 so you may not have all of these in the sheeva repo)

Code:

sudo apt-get install libusb-0.1-4 libusb-dev

I doubt you have room for this since one of it's dependencies is qt4-doc which takes 51M alone, but you can install qt4-dev-tools in you need/want the qbusviewer. I found it handy but you can do without it.

Code:

sudo apt-get install qt4-dev-tools  #(optional)

Get the tarball on the device and build with

Code:

tar xzf fbd.tar.gz 
cd fbd/
qmake
make

Then you need to copy one file to be able to run the daemon

Code:

sudo cp FusionBrain.conf /etc/dbus-1/system.d/

At this point you may need to restart dbus (not sure but it can't hurt)

Code:

sudo /etc/init.d/dbus restart

With your Fusion Brain plugged in start fbd as root

Code:

./fbd

And you should see something like

Code:

root@jaunty:/home/cgalpin/fbd# ./fbd 
Fusion Brain V4 found!
Attempting to open interface...
Fusion Brain connected!

If you want to just test from the commandline you can use dbus-send

Set the first digital output on (you should see the lcd come on)

Code:

dbus-send --system --print-reply --dest="org.openice.fbd" /org/openice/fbd org.openice.fbd.fusionbrain.SetSingleOutput int32:0 boolean:true

Turn off the 3rd digital output

Code:

dbus-send --system --print-reply --dest="org.openice.fbd" /org/openice/fbd org.openice.fbd.fusionbrain.SetSingleOutput int32:2 boolean:false

And so on. I ran into problems reading analog output and I think the daemon is only partially completed but its a great start!

I also tried a php-dbus package (seems to be anothr one being developed for pecl, but it's not ready yet). It's easy to try.

Download and install:

Code:

wget http://labs.gree.jp/data/source/php-dbus-0.1.2.tgz
tar xzf php-dbus-0.1.2.tgz 
cd php-dbus-0.1.2/
phpize
./configure
make
sudo make install

You'll need to add this to your php configuration and the most maintainable way is to add a file to /etc/php5/apache2/conf.d You need to be root to do this and an easy way is

Code:

sudo su -
echo "extension=dbus.so" > /etc/php5/apache2/conf.d/dbus.ini
^D

I also found the default memory settings were too low so you might as well fix that up front. Edit php.ini as root

Code:

sudo vi /etc/php5/apache2/php.ini

And change memory_limit = 16M to memory_limit = 32M (although even at 32M i get the occasional memory error with this)

You will need to restart apache for these changes to be picked up

Code:

sudo  /etc/init.d/apache2 restart

Now you can make a test script - say /var/www/dbus.php and run it as http://PLUGIP/dbus.php

On my system I had to create the file as root and give my non-root user ownership or you can just edit it as root. Here is a little script to turn the digital outputs on/off

# turn digital output 0 on
http://PLUGIP/dbus.php?do=0&value=1


# turn digital output1 off
http://PLUGIP/dbus.php?do=1&value=0

and so on.

PHP Code:

<?php

$do = isset($_GET['do']) ? (int)$_GET['do'] : 0;
$value = isset($_GET['value']) ? (bool)$_GET['value'] : true;
$timeout = 1; # seconds
echo "Setting digital output $do to " . ($value ? "true" : "false" ) . "..</br>";

$dbus = dbus_bus_get(DBUS_BUS_SYSTEM);
if ( $dbus )
{
  $m = new DBusMessage(DBUS_MESSAGE_TYPE_METHOD_CALL);
  if ( $m )
  {
    $m->setDestination("org.openice.fbd");
    $m->setPath("/org/openice/fbd");
    $m->setInterface("org.openice.fbd.fusionbrain");
    $m->setMember("SetSingleOutput");
    $m->setAutoStart(true);
    $m->appendArgs($do);
    $m->appendArgs($value);
   
    $r = $dbus->sendWithReplyAndBlock($m,$timeout);
    if ( $r )
    {
      $tmp = $r->getArgs();
      echo "Got reply:<br/>";
      print_r($tmp);
    }
  }
}
?>

Oops - looks like I got a little caried away with the code blocks

hth
charles