[Solved] Cyanogenmod 7.2.0.1 - WIFI disconnects after display is off

I had installed Cyanogenmod 7.2.0.1 in my mobile. It is really an awesome OS!

After installation of the OS in my mobile, I had set the WIFI sleep policy to 'When screen turns off'. The problem I faced because of this setting was when my mobile display was off, WIFI would get disconnected and mobile data connection was switched on automatically; this caused my available mobile data allowance per month to be used, even though there was a WIFI available.

I totally forgot where I had set this policy. I literally browsed all the settings except, where it could be re-configured! Finally I found where I had set the WIFI sleep policy, and set it back to 'Never'.

In this post I will provide the steps on how to set the WIFI sleep policy to suit your need.

1. Open Settings
2. Navigate to Wireless & networks > Wi-Fi settings
3. Press the menu button on phone
4. From the menu, select 'Advanced'
5. Open 'Wi-Fi sleep policy'
6. Select the option that suits your need ( I set it to 'Never' )

No worries of WIFI disconnect after this setting was enabled.

[Solved]: Ubuntu 11.10 wireless very slow in Dell XPS M1530

In one of my previous posts about slow internet connection experienced in Ubuntu 11.04, I could not solve the problem and finally I had to downgrade my laptop to Ubuntu 10.10.

Today's post is about slow wireless connection experienced in my Dell XPS M1530 laptop after installing Ubuntu 11.10 and how this problem was solved.

In my laptop I have installed Ubuntu on dual boot, along with Vista SP2. The wireless speed from Vista SP2 was fairly fast (after I manage to open a browser and try to download in Windows after long wait to boot and finally another long wait after double clicking on the browser application). So I concluded, the slow wireless speed in Ubuntu is something to do with the driver of the wireless adapter that is installed. From the information I got from lspci command, I searched for Linux driver for my wireless adapter, but I couldn't find any. Finally I got information about an utility in Ubuntu that allows installation of drivers which are released by the manufacturers for Windows OS. That is brilliant. I gave it a shot and got excellent speed in my WiFi connection.

I am listing below the steps that I followed to fix the wireless problem and get the WiFi connection to full speed on my laptop.

1. Downloaded the drivers (.exe files) from dell.com for Windows OS. These driver packages (.exe files) are self extracting zip files, which can be opened and extracted using Archive Manager in Ubuntu
2. Extract the downloaded drivers
3. Using 'Package Manager', search for 'ndisgtk' and install ndisgtk
4. Open 'Wireless Network Drivers', and click 'Install New Driver'
5. Locate the .inf file from the extracted location above and click 'Install'
6. In the 'Wireless Network Drivers' the driver will be listed with status Hardware Present: Yes

Hope this helps. :-)

An error occured in avast! engine: Invalid argument

I recently installed Avast4Workstation in my laptop running Ubuntu 10.10. The avast engine was able to do a complete scan of my system. After that I decided to fetch latest updates for avast and clicked 'Update database' in the GUI. After the update happened, the avast will not open, but shows the error message

An error occurred in avast! engine: Invalid argument

Solved:
In older kernels the maximum size of SHM block was limited to a certain number of bytes, that is being exceeded by the database. We need to increase the size of the SHM block to accommodate the large database
The command to be executed in the terminal is as follows. When executing the command it will ask for the root password.
sudo sysctl -w kernel.shmmax=128000000
The above command provided me with a temporary solution to the problem I was facing. After I restarted my machine, if I wanted to open avast, I had to type the command again. To get away with this, there is another way.

Add the line kernel.shmmax = 128000000 to the bottom of the sysctl.conf text file.
How to update the sysctl.conf file:

1. Go to 'etc' folder, select sysctl.conf file
2. With the sysctl.conf file selected, press Alt + F2. This will open the 'Run application' dialog
1. Type gksu gedit
2. Add kernel.shmmax = 128000000 to the file and save

Calendar Active Exchange Sync on Android : Client/server conversion error

I happened to edit one of the occurences of a recurring meeting, in my mobile's calendar. My mobile is having Android Froyo (Android 2.2). After editing, I connected my phone to wifi and tried to sync the calendar. But when I tried to sync, the calendar will not successfully sync, but shows the error "Client/server conversion error".

This is how I solved the problem:

1. In my phone, I navigated to Settings > Applications > Manage Applications. Selected 'All' tab which shows all the applications.
2. After that I scrolled to Calendar in the list I did the following
1. Seleted and opened the Calendar from the list.
2. Clicked on 'Clear Data'.
3. I repeated steps above 2(a) and 2(b) for 'Calendar Storage', 'Calendar Sync Adapter' & 'Calendar Widget' in the list of applications, that I had opened in step 1.
4. I clicked the 'Home' button on my phone to go to the home screen. Then again navigated to Settings > Accounts & Sync > Exchange ActiveSync.
1. Unchecked 'Sync calendar'
2. Clicked 'Sync now' (synced Mail & Contacts only)
3. Checked 'Sync calendar'
4. Clicked 'Sync now' again. (synced Mail, Calendar & Contacts)

The error has never come back again.

But not sure why a calendar item if I modify in my phone cannot be synced to the calendar in the exchange server.

VM Player - Disk space - Shrinked

The disk files created for the Virtual machine in my PC constantly grew in size until the whole of the host drive was used up.

I could not possibly find what would have gone wrong, because inside the virtual machine, the disk space utilized was not compensating to the usage of the host disk space usage.

Things I have done to get the disk space usage within limit.

1. Open VM Player, select the virtual machine, Click Edit Virtual Machine Properties.
• Select the disk drive and from the utilities dropdown list select "Defragment Disk"
2. After starting the virtual machine, open the VM tools and go to "Shrink", select the disks to shrink and shrink.
• Problem I faced while shrinking was, there should be enough space available in the host drive for the shrink to happen.

Video/Audio Problem - Google Talk

I was not aware about how to change the camera/microphone options in google talk. Because of this, even if I plug-in my USB webcam in my laptop, I wasn't able to use it, but google talk was only detecting the integrated laptop webcam.

Recently I found in google support forum, that the settings can be changed to configure the camera and microphone.

How I did it is, in gmail go to Settings > Chat.

Make necessary changes in the set of available devices and click Save.

Bingo!

VM Player - Freeze Intermittently - Problem

For the past couple of days the VM player that I am using was getting frozen for 15-20 seconds. This occurred at a frequency of 1 Hr everyday. I did not have any idea what had gone wrong, until I noticed the previous week the LAN configuration at my work had changed. It gave me a clue that the problem is due to the network, but why is my VM player in need of a network connection, when all I need to access resources locally.

I started troubleshooting the issue, around the clue that the VM player needs network access, but what for I was not clear. Some of the candidates that were considered for further investigation were
Local Folder Map
Internet Access

The local folder map was stroked off from the list as I found it did not have anything to do with the recent LAN change.

The next candidate was Internet Access, and it was the right candidate to put my effort to find the root cause of the problem. In the preferences of the VM Player, I had opted for software updates. I unchecked the checkboxes that made the VM player to check for updates and finally the VM player performance problem was fixed.