Archive for October, 2009

Eee PC: WiFi Problems on the Road

October 16, 2009

I took my Eee PC on its first road trip last weekend.  Things didn’t go exactly as expected; Eee PC wise that is.  For those of you who are not regular readers of my blog, I would like to point out that this discussion pertains to the Linux version of the Eee PC.

Like most NetBook owners, one of the things that attracted me to the Eee PC was the portability.  I was looking forward to traveling with a computer that was no heavier or larger than a hardback novel.  I already knew that my hotel, favorite coffee shop and favorite book store at my destination had free WiFi.  It was time to say goodbye to that back ache I always developed when I traveled with my older laptop computer.

The first hint of trouble came even before I started my trip.  While I was waiting around at the Seattle airport, I decided to check my emails.  Strangely enough, the Eee PC could not see any wireless access points.  I didn’t give it much thought at the time as it was time to pack up and board the plane.  A few hours later I had arrived at my destination and checked into my hotel.  I was eager to get on line and check my email as I was off line for nearly eight hours.

I imagine that some of you are thinking, if the Denki-Guy wants to stay connected, why doesn’t he use a smart phone for email?  That is a good question and the answer is simple.  The Denki-Guy is cheap.  Back when I used my phone more, monthly bills in excess of $200 were not unusual.  This seemed excessive to me, especially when free WiFi is available at more and more places.  I have seen free WiFi advertised at coffee shops, book stores, car dealers, medical offices, beauty salons and more.  I generally have no problem checking my emails every couple hours or so.

Now back to my story.  Soon after I dropped my bags in my room, I pulled out my Eee PC and booted.  It typically takes about a minute before I see that little balloon that says, “Wireless Networks Detected.”  I waited patiently for two and then three minutes.  Nothing.  I tried to create a new network connection from scratch but when it came time to select a wireless network from the list, no networks could be found.  Expletive deleted!

That evening I tried a number of things to get my wireless connection to work.  I tried rebooting.  I tried cleaning out old connections.  I tried going to other locations within the hotel.  I tried going to a book store with free wireless.  Nothing worked.  Finally, the hotel lent me a gaming adapter that converted WiFi to a wired network connection.  I was finally on line.

My tale of woe is still not over.  The next morning, I awoke my Eee Pc from sleep mode and it seems that the wired connection had failed also.  The log told me that the network stack never received an IP address from DHCP.  More expletives deleted.  I didn’t have time to dwell on the topic though, I had meetings to attend.

Now here comes the strange part.  I arrived back at my hotel some 12 hours later and I was determined to get to the bottom of this problem.  I booted up the Eee PC and I was shocked when I saw the Wireless Networks Detected balloon appear.  I chose a network that had 100% signal strength and within seconds I had a wireless connection.  What is going on?

During the rest of my trip, the WiFi connection on the Eee PC worked fine.  I added connections for the book store, coffee shop and airport access points.  Once and a while, I would get a message that the Eee Pc could not connect to a certain access point but after chosing re-connect in the Networks control, I would get a connection.

I wish I could tell you what is going on but I don’t know for sure.  In theory, this is a computer and it should work the same way every time.  In reality, most modern computer systems act like organic systems; they are so complex that it is extremely difficult to figure out what exactly is going on.  In this case, I suspect a startup race condition (read timing problem).  For some reason, a certain process does not start up which causes problems with all the components with dependencies.

What to do if you no wireless networks are found (but you know an access point is indeed available)

  1. Restart the computer and try again.
  2. Turn the computer off, wait a minute or so and try again.
  3. Turn the computer off, unplug the AC adapter, remove the battery, let the computer cool down 5 minutes or more, reassemble everything and try again.

The next time this happens, I will take some more time to try to figure out which process is not starting up correctly.  If I can pinpoint the problem, I will post a better solution to this problem.

The Denki-Guy


Translation of GMC-4 Manual Pages

October 15, 2009

Recently, I have noticed a significant up-tick in the number of visitors to my posts on Otona no Kagaku Magazine, volume 24.  I hope that this means that more folks outside of Japan are getting their hands on this magazine and more importantly, the 4-bit Microcomputer.

For the benefit of those who are not fluent in Japanese, I have decided to translate the GMC-4 Manual pages contained within the magazine.  I have just finished the first section and published it as a separate page.  You will also find a link to this page to your right under Pages.

I decided to publish the original Japanese and my English translation side by side for the benefit for those studying Japanese.  My teenage daughter tells me that a lot of kids in high school take Japanese so they can read manga in the original Japanese.  I would love to hear about teenagers taking up Japanese to learn about Japanese technology and other cool stuff from companies like Gakken, the publisher of Otona no Kagaku.  I can’t be the only one.

The Denki-Guy

(Okay, I didn’t exactly take up Japanese in high school.  I started studying Japanese at age 23.)

Changing the Computer Name of your Eee PC

October 3, 2009

The Denki-Guy has been using his new Eee PC 900, Linux model for a couple months now.  After a number of configuration changes documented in these pages, I have my little NetBook working nicely.  Yet … there is one thing that was still bugging me.  Using my Windows system, when go to View workgroup computers (from My Network Places), my NetBook is advertised as follows:  “asus-505051062 server (Asus Eee PC) (asus-505051062)”.  I’m not kidding.  Now you know why it has been bugging me.

This long name comes from two places: the Computer Name and the Samba server string.

Computer Name is a generic term for the name used to identify you computer on the network.  In Unix/Linux, host name is used instead of computer name.  The host name of my computer, before I made the change, was “asus-505051062”.  I imagine that  Asus generates the number portion of the name at their factory to give each Eee PC a unique name.  Thank you for the good work Asus but it is now time to select a new host name.  A host name consists of 1 to 15 alphanumeric (A-Z, a-z, 0-9) characters with no spaces or special characters other than hyphen (-).  There is a good article from Microsoft on naming conventions.  It would be good idea to read the “Best practices” section before choosing a name.

The Samba server string is the “asus-505051062 server (Asus Eee PC)” portion of the NetBook advertisement.  You have probably noticed that the host name appears in the server string.  This was done intentionally.  I know this by looking at these lines in the Samba configuration file, smb.conf.

# server string is the equivalent of the NT Description field
   server string = %h server (Asus Eee PC)

Note the %h in the server string.  The percent sign preceeding a single character represents a Samba server variable.  In this particular case %h represents the DNS hostname.  The Server variables are a way to insert machine specific information into the configuration file.  You do not need to include the host name in the server string but you can is you want.  A list of all the server variables can be found in table 6-2 of this document.  I tried to find some information on maximum string length or disallowed characters for the server string but I could not find anything specific.  That said, I think it is best to keep this string brief.

Now that you have all the background, let’s go to work.

Changing the host name (Computer Name)

  1. Press CTRL + ALT + T on the keyboard to bring up a terminal  screen.
  2. Type sudo xedit /etc/hostname  ENTER in the terminal window.  A xedit window will appear.
  3. Delete the old name and enter the new host name you have chosen.  The new host name I chose was “netbook-101"
  4. Click on the xedit Savebutton twice.  Close xedit.
  5. Type exit ENTER in the terminal screen to close the window.

Changing the Samba server string

  1. Press CTRL + ALT + T on the keyboard to bring up a terminal  screen.
  2. Type sudo xedit /etc/samba/smb.conf  ENTER in the terminal window.  A xedit window will appear.
  3. Look for the line that says server string = %h server (Asus Eee PC)
  4. Change the right side of the server string assignment to reflect the new string you chose.  In my case server string = My White Eee PC 900.
  5. Click on the xedit Save button twice.  Close xedit.
  6. Type exit ENTER in the terminal screen to close the window.
  7. Restart the Eee PC.

After your Eee PC reboots, wait a minute or so and then from your Windows PC go to My Network Places -> View workgroup computers.  You should see both the new server string and the machine name on the page.  My Eee PC is now advertised as “My White Eee PC 900 (Netbook-101)”.  Note how Windows did me a favor and capitalized the first letter in Netbook.  I double checked and indeed, the computer name on the Eee PC side is all lower case.

The Denki-Guy