Craig Mayhew’s Blog

Ubuntu versions 10.04 and 10.10 had various issues with the screen brightness on my HP EliteBook 8530w. It wasn’t possible to adjust the brightness which was a real problem if the screen dimmed while power saving.

The only fix I’ve found was to update to Ubuntu version 11.04.

If you get the following error when your upgrading:

An unresolvable problem occurred while calculating the upgrade:
Trying to install blacklisted version ‘blcr-dkms_0.8.2-13′

To fix, simply search for the package ‘blcr-dkms_0.8.2-13′ in package manager and mark for upgrade. Click apply and then try the system upgrade once again.

This command will mount a windows share on Ubuntu 10.10 (and obviously other versions):

sudo mount -t cifs //1.2.3.4/ShareName/ /media/share -o username=yourUserName,password=yourPassword,allow_other

“1.2.3.4″ – The name of the server with the share
“ShareName” – The name of the shared folder
“/media/share” – The local folder the share will be mounted to
“yourUserName” – The username for the share
“yourPassword” – The password for the share

If you don’t have a password, you really should have one for security but here is the command anyway:

sudo mount -t cifs //1.2.3.4/ShareName/ /media/share -o allow_other

If you get the error:

mount: //1.2.3.4/ShareName/ is not a valid block device

Then you may need to install samba file sharing:

sudo apt-get install smbfs

It appears one of the updates to the linpus linux operating system used on Asus Aspire One netbooks messes up the networking. In short the permissions get set wrongly on the network settings files. Symptons include, not being able to see the network icon on the menu, clicking “Network Settings” icon on the settings page and having nothing happen etc..

Before you run this fix, please understand that you will lose all your saved network connections and you will need to add in your network keys again.

To fix:

Press Alt+F2 and a run box should appear.
Then write “terminal” and click “Run”.
In the new terminal windows that has appeared type “sudo gconftool-2 –recursive-unset /system/networking” to clear all the root network connections.
Then type “gconftool-2 –recursive-unset /system/networking” to clear all the user network connections.
Reboot the netbook and the network icon appears again after about 20 seconds but you need to reconfigure the network connections again by adding passwords etc…

If this hasn’t fixed your problem then this forum has loads more info on the subject http://www.aspireoneuser.com/forum/viewtopic.php?f=34&t=2620&sid=7ee9a1caf5a8ccaf10dd281ac6caf861. I recommend reading the whole forum thread before trying the solutions, as you may want to try easier ones first!

The noatime option tells an ext filesystem to not update the “last accessed” timestamp every time a file is opened. This enables you to save disk i/o and have you disk caches perform much better.

You need to edit the fstab file to use the noatime option.

sudo vim /etc/fstab

Your fstab file will look different to this. At this point I should warn you that if you mistype this, delete something you shouldn’t or otherwise break this file, you Linux system MAY NOT BOOT. You can see below where I have added noatime which is visible in bold.

/dev/hda1 / ext3 defaults,errors=remount-ro,noatime,auto 0 1

Reboot and if all is well then you should have a faster filesystem.

If you ever manage to damage your ubuntu install so badly that it won’t boot (as I recently did when trying to remove the gnome GUI) then boot from a LiveCD and then open up a terminal.

Type the following commands:

change to the media directory (where our drives should be)
# cd /media

Create a new directory called Ubuntu (We will use this to mount our boot drive too)
# mkdir ubuntu

Mount the boot drive, you will need to replace X with the correct letter
# mount /dev/sdaX /media/ubuntu

Mount some other required locations
# mount –bind /proc /media/ubuntu/proc
# mount –bind /dev /media/ubuntu/dev
# mount –bind /dev/pts /media/ubuntu/dev/pts

Run chroot, using this command and we are now root as if we had booted from the boot drive and not the liveCD:
# chroot /media/ubuntu

Your now in your Ubuntu system as root. If your unsure precisely why your system won’t boot then running an update is usually a good place to start. Good luck!
# aptitude update

I recently tried installing a .deb packagae I had made by converting an rpm. Synaptic package manager however errored and since then won’t open. Every time I started synaptic I was getting this error:

The package vmware-server needs to be reinstalled, but I can’t find an archive for it

This command solved it and will force the removal of my incosistent package:

dpkg --remove --force-remove-reinstreq vmware-server

After a fresh install of Ubuntu Karmic I found that the additional hard drives kept asking for a password each time I logged in and accessed them for the first time.

To fix the problem, simply install pysdm:

sudo apt-get install pysdm

Then run it as root:

sudo pysdm

Choose your device and then mount your partitions accordingly.

One easy command to retrieve all drive UUIDs.

ls -lF /dev/disk/by-uuid

The usual reason for not being able to update the scripts is that your permissions are wrong in your Firefox folder. Your Grease Monkey scripts will be in your firefox folder. The default place for this is (please substitute {username} for your actual Ubuntu user name):

cd /home/{username}/.mozilla/firefox/gm_scripts/

You need to make sure you are the owner of this folder. This command will make sure you are. Again please substitute whats inside the {} brackets.

chown -R {username}:{usergroup} /home/{username}/.mozilla/firefox/gm_scripts

If that still fails to fix the problem, then you also need to make sure you have write permissions on your firefox settings folder.

chmod -R 755 /home/{username}/.mozilla/firefox/gm_scripts