Craig Mayhew's Blog » Linux/Ubuntu

Asus Aspire One network manager applet disappeared!

Craig Mayhew — Mon, 19 Apr 2010 20:00:33 +0000

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!

noatime

Craig Mayhew — Wed, 07 Apr 2010 07:00:06 +0000

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.

Chroot in Ubuntu

Craig Mayhew — Tue, 30 Mar 2010 06:43:17 +0000

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

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

Craig Mayhew — Mon, 29 Mar 2010 07:00:14 +0000

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

Modifying fstab to prevent password requests before mounting a hard drive

Craig Mayhew — Sun, 28 Mar 2010 07:00:29 +0000

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.

Retrieve Drive UUIDs in Ubuntu

Craig Mayhew — Sat, 27 Mar 2010 14:20:48 +0000

One easy command to retrieve all drive UUIDs.

ls -lF /dev/disk/by-uuid

Greasemonkey scripts won’t update on Ubuntu

Craig Mayhew — Sun, 07 Feb 2010 20:11:00 +0000

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

Finding Files in Linux

Craig Mayhew — Tue, 08 Dec 2009 13:12:49 +0000

Find “text to find” in files within the current directory

grep -lir "text to find" *

Find “example” in filenames within the current directory

find -name '*example*'

Find a file called “example.txt” within the current directory

find -name 'example.txt'

Find all files larger than 1000k within the current directory

find -name '*' -size +1000k

Slow DNS Lookups in Firefox on Ubuntu 9.10 Karmic Koala

Craig Mayhew — Sat, 07 Nov 2009 15:15:11 +0000

Unfortunately the IPv6 issue is still at large in Karmic Koala and will effect just about every internet application.

The problem is caused by Ubuntu requesting everything by IPv6 first even if there are no IPv6 Interfaces configured and timing out each time when it doesn’t get a response.

The workaround in firefox is to go to “about:config”, just type it into the address bar and hit enter. Then change the value network.dns.disableIPv6 to TRUE.

The bug can be tracked here:
https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/417757

Setting Up PPTP VPN in Ubuntu 9.10 Karmic Koala

Craig Mayhew — Thu, 05 Nov 2009 07:00:21 +0000

Ubuntu 9.10 doesn’t come with VPN connectivity out of the box. So you need to install 3 packages to get it to work. Symptoms of these packages not being installed are grayed out “Add” buttons and grayed out “Apply” buttons in the VPN connection manager.

Here’s the command to install the 3 packages:

sudo apt-get install network-manager-pptp network-manager-vpnc network-manager-openvpn

I have no idea why Ubuntu doesn’t include these packages by default. Looks like a great many people are having this issue: https://bugs.launchpad.net/ubuntu/+source/network-manager-pptp/+bug/107738