Connecting to the Internet from Ubuntu using bluetooth to a Nokia E65

Having just set this up for about the 4th time, I thought it was about time to record what I actually do - rather than working it out each time!

First off, I get the phone and laptop paired - easy enough using the bluetooth icon on the gnome panel.

Then, edit /etc/bluetooth/rfcomm.conf to look like:

#
# RFCOMM configuration file.
#

rfcomm0 {
# # Automatically bind the device at startup
bind yes;
#
# # Bluetooth address of the device
device 00:AA:BB:CC:DD:EE;
#
# # RFCOMM channel for the connection
channel 2;
#
# # Description of the connection
comment "Nokia E65";

}

using the appropriate device MAC. If you don't know this then
hcitool scan

will reveal devices that are visible in your locality and then
sdptool browse

will let you find the channel number for Dialup Networking.

Restart bluetooth after this change.

Next create /etc/ppp/peers/orange

noauth
#change this if you move the path to your connect script
connect "/usr/sbin/chat -v -f /etc/chatscripts/orange-connect"
#change this if you move the path to your disconnect script
disconnect "/usr/sbin/chat -v -f /etc/chatscripts/orange-disconnect"
#I found that I needed this to remove problems with loopback on connecting
silent
#remove this if you don't want lots of information going to /var/log/messages
debug
#this is the device specified in your rfcomm.conf file
/dev/rfcomm0
#speed at which to connect - might be worth trying higher...
115200
#this is needed so that a default route is added to your routing table
defaultroute
#this is needed so that you pick up Orange's DNS settings
usepeerdns

lcp-echo-failure 0
lcp-echo-interval 0
nomagic
noccp

And /etc/chatscripts/orange-connect:

TIMEOUT 5
ECHO ON
ABORT '\nBUSY\r'
ABORT '\nERROR\r'
ABORT '\nNO ANSWER\r'
ABORT '\nNO CARRIER\r'
ABORT '\nNO DIALTONE\r'
ABORT '\nRINGING\r\n\r\nRINGING\r'
'' \rAT
TIMEOUT 12

OK ATE1
#here's the magic bit!
OK 'AT+CGDCONT=1,"IP","orangeinternet"'
OK ATD*99***1#
TIMEOUT 30
CONNECT ""

And /etc/chatscripts/orange-disconnect

ABORT "BUSY"
ABORT "ERROR"
ABORT "NO DIALTONE"
SAY "\nSending break to the modem\n"
"" "\K"
"" "\K"
"" "\K"
"" "+++ATH"
"" "+++ATH"
"" "+++ATH"
SAY "\nPDP context detached\n"

With all this in place, sudo pon orange should make the connection and sudo poff orange should break it.

Scanning documents using SANE and an ADF on a Fujitus M4097Ddm

Working on a document scanning project to sort out some paperless office systems, I came across an interesting problem while using the ADF on our Fujitsu M4097Ddm scanner.

The command scanimage -y 297 --source="ADF Front" resulted in a message back from sane of

scanimage: rounded value of br-y from 297 to 279.364

I.e. the page was getting truncated to US Letter length - not very helpful.

The solution is to change the order of the parameters and add an extra one:

scanimage --source="ADF Front" --pageheight=297 -y 297

Once the document source is specified then the list of available options changes and the pageheight and pagewidth options become available.

Permissions on USB devices on LTSP terminals

In our linux environment, all our users have the same primary group, rather than having a private group. For the vast majority of stuff this is fine and keeps things simpler. However the method that ltsp uses for mounting USB sticks (or other local media) creates a directory called /media/ on the server which is has the group set to the primary group of the user and the owner set to root with permissions of rwxr_x___

This, combined with the users all being in the same primary group leads to the devices that users plug in being shown on all users' desktops. They can't actually access the devices - those have different permissions - but they can see their existence which at the least is annoying and in the case of several people using CD drives, confusing.

My current solution is a little convoluted - but does the trick.

Firstly you need a program that can change ownership of a directory. This has to be installed as a suid program as the mounting script is run by the user who is logged into the terminal.

I just have a little piece of C to do the job:

#include
#include
#include

int main(int argc, char *argv[]) {

char buff[100];

if (argc != 2)
exit(1);

sprintf(buff, "/bin/chown %s:root /media/%s", argv[1], argv[1]);
system(buff);

return(0);
}

I call this program mediafix and have installed it in /usr/local/bin

Then, in /usr/sbin/ltspfsmounter, add a line saying

call(['mediafix'], username)

towards the end of the main function after the mounting has taken place.

This ensures that any time a device is mounted, the containing directory has it's ownership amended and keeps the icons hidden from other users.

Debian Lenny on a Poweredge 2600

Usually the Debian upgrade procedure is pretty straight forward, and my recent upgrade of a Poweredge 2600 from etch to lenny was no exception. Just change the sources and do an apt-get update; aptitude dist-upgrade and answer some questions along the way.

Occasionally there's a gotcha - and this one had an issue with our lvm based file system. Using the new kernel that comes with lenny (2.6.26), it failed to find the lvm and therefore wouldn't boot.

A little googling revealed a potential solution - add the option "rootdelay=9" to the kernel options for boot - and surely enough the machine was back to life.

Flashing the firmware on a 3c905c network card

There's two revisions of the 3C905C out there. The earlier one has an issue when using boot code on the card in that you can't make use of the "next server" option in your dhcp config - it simply fails to boot from the correct server reporting a timeout during the TFTP.

The later version works fine - so here's the trick - take the firmware from a later one and flash it to the earlier.

Using a debian box this is relatively simple.

Install the etherboot package to get the tools needed.

Then in /usr/share/doc/etherboot/contrib/3c90xutil/ gunzup cromutil.c.gz and bromutil.c.gz

Make sure you have built-essential on your system and then use make to compile the tools

Now, with the good card in the system, do

lspci -v | less

and look for the ethernet controller. Make a note of it's I/O port address (ours was a000

Then to get the rom image type

./cromutil [ioport] read > [imagename]

e.g.

./cromutil a000 read > working.rom

Now shut down the machine and replace the good card with the one that needs programming

Once you've booted back up, go to /usr/share/doc/etherboot/3x90xutil/

Use lspci -v again to check the address of this card

Then do

./cromutil [ioport] erase
./cromutil [ioport] prog < [imagename]

You should now have a card programmed with the later firmware and capable of correct remote booting where the boot host is other than the dhcp host.

Using LDAP for email aliases

As I gradually migrate various servers to using LDAP as the auth back end, it occured to me that there was some duplication going on in terms of adding the users' email addresses to the LDAP so that they could be looked up on clients and then having an aliases file that was being used by exim to do the delivery.

So I've come up with the following for allowing exim to take advantage of the email addresses stored in the LDAP database:

### router/450_local_ldap_aliases
#################################

# This router handles aliasing looking up email addresses in an ldap database.
#

ldap_aliases:
debug_print = "R: ldap_aliases for $local_part@$domain"
driver = redirect
domains = +local_domains
allow_fail
allow_defer
data = ${lookup ldap {ldap://127.0.0.1/ou=Users,dc=...?uid?sub?(mail=$local_part@$domain)}}

Ubuntu on a Dell XPS M1530

With the release of Ubuntu 8.10 (Intrepid Ibex) the vast majority of stuff on a Dell XPS M1530 works out of the box. One caveat is the touchpad. It jumps around like a demented rabbit!

The solution is simple.

Edit /boot/grub/menu.lst

Find the line that starts
# kopt=root=UUID....

Add i8042.nomux=1 to the end of that line

Then run update-grub and reboot.