Problems connecting to WiFi from 24" aluminum iMac

I finally solved my problem connecting to my wireless router. I couldn't believe that I was having more luck connecting to my neighbour's unsecured WiFi connection than to my wireless modem/router (a Billion 7300G) in the same room.

My wireless setup was:

Channel 6
WPA-PSK
Encryption: AES

Now all along I was thinking it was one of these reasons:

1. the Airport card was faulty
2. it was an OS X config problem - WPA2 encryption-related
3. it was a Leopard problem

Now I was really hoping it wasn't #1, because it would have been a royal pain in the ass to try and send back a 9kg computer in the mail. It didn't seem likely because I was able to connect to my neighbour's wifi network without problem. Which leads us to #2 - well, no way was I going to leave my connection unsecured, but just to test out this theory, I turned off the wifi security for a while. And for a couple of times it worked - I could connect to the network and use a browser, etc. Until it stopped doing it.

The last one was #3, and I was all ready to update to 10.5.1 - but I remembered that when I first set up my wireless connection I was using Channel 1. I moved to Channel 6 because I was getting some trouble connecting from the Powerbook downstairs. So I hooked up the iMac to the router, changed to Channel 1, unplugged from the router - voila! all working!

I later found a forum posting (http://discussions.apple.com/thread.jspa?messageID=1822533#1822533) which claimed that Apple engineers had mentioned a conflict between Bluetooth and Channel 6 on wifi. Looks like that was the problem I was having. Bluetooth is on by default, so I turned it off. But I haven't changed the router back to Channel 6. I figure it's better to leave things alone once they work!

Solution to Problem:

4. change wireless channel from channel 6 to channel 1. In some cases Channel 6 conflicts with Bluetooth. So either turn off Bluetooth or stop using Channel 6.

To get listing of directories use ls -d */

I've been trying to get a listing of the directories contained in two
different directories so i can compare their contents. The usual 'ls'
returns too much info. Finally got it working with:

ls -d */

- gets listing of directories ending in /
- will not get the '.' entry

Problems installing mysql gem on Centos? Try installing the mysql development headers first

Was trying to install the mysql gem on a Centos linux server, but was having a problem. It was like:

> gem install mysql
Updating metadata for 6 gems from http://gems.rubyforge.org
......
complete
Building native extensions. This could take a while...
ERROR: Error installing mysql:
ERROR: Failed to build gem native extension.

/usr/bin/ruby extconf.rb install mysql
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lm... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lz... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lsocket... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lnsl... yes
checking for mysql_query() in -lmysqlclient... no
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers. Check the mkmf.log file for more
details. You may need configuration options.

Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/usr/bin/ruby
--with-mysql-config
--without-mysql-config
--with-mysql-dir
--without-mysql-dir
--with-mysql-include
--without-mysql-include=${mysql-dir}/include
--with-mysql-lib
--without-mysql-lib=${mysql-dir}/lib
--with-mysqlclientlib
--without-mysqlclientlib
--with-mlib
--without-mlib
--with-mysqlclientlib
--without-mysqlclientlib
--with-zlib
--without-zlib
--with-mysqlclientlib
--without-mysqlclientlib
--with-socketlib
--without-socketlib
--with-mysqlclientlib
--without-mysqlclientlib
--with-nsllib
--without-nsllib
--with-mysqlclientlib
--without-mysqlclientlib


Gem files will remain installed in /usr/lib64/ruby/gems/1.8/gems/mysql-2.7 for inspection.
Results logged to /usr/lib64/ruby/gems/1.8/gems/mysql-2.7/gem_make.out

I managed to fix it by installing the mysql development headers first. We had already downloaded it onto the server, so instead of using yum, we used rpm -i to install it. Yum wouldn't have worked anyway, because we were using Mysql 5.1.22, which is not yet on the yum repository (only 5.0.45 is there).


rpm -i MySQL-devel-community-5.1.22-0.rhel5.x86_64.rpm

[root@cr1sescl01 mysql]# gem install mysql
Updating metadata for 32 gems from http://gems.rubyforge.org
................................
complete
Building native extensions. This could take a while...
Successfully installed mysql-2.7
1 gem installed