I'm sitting here in school on my slackware laptop.
I followed T3slider and in 5 min all was working.
Amazing support you all gave me so fast.
This I will do next time I have a big problem:).
I added some DNS servers into the /etc/hosts and
setup the proxy without the script. I tried that before without
the DNS servers in the /etc/hosts and i didn't worked.
but now I have learned something I can tell the schools admin...
hahahah!
;)

Just don't forget that this is a very ugly workaround. It is just wrong for users to have to worry about DNS and proxy. In our school, folks just use one of the available desktop clients (running Slackware :D) or their own laptop (running Windows XP/Vista/Seven, Mac OS X, Ubuntu Linux), eventually connect to the wireless access point and use the (filtered) Internet. Zero hassle for them.

Hi,

I use to set http- and ftp-proxy as invironment-variables when I'm at work.
Provided the proxyserver has IP-adress 192.168.52.240 on port 8080, you could execute the following commands
and configure firefox to recognize the systems-network-settings.
I'll upload an attachement to this posting, there you can see the settings for firefox. It should also work if you put the url of the pac-script into the "Automatic proxy configuration URL".

The advantage of using http_proxy and ftp_proxy as environment-variables is that this also works with wget (for example).

Markus

I want to add an explanation referring to Windows. Today I've read our proxy.pac script at work.

When you configure the networksettings on a Windows-computer in the ie (Internet-Explorer), you configure the systems networksettings, they are the same. The ie-settings represent the system-wide settings. This means that particularly other programs on a Windows-computer (for example Flashplayer when updating) use the same networksettings and "know" the correct proxysettings.

The proxy.pac script is simply javascript and should work in any browser, even on a Linux-computer!

The difference between Linux and Windows referring to these settings is that on Linux there is no ie (or other browser) which represents the systemwide proxysettings.

I don't know how this issue is solved in networks where there are Linux and Windows-computers (I use environment-variables as I wrote above). It should be possible, to write a shellscript which does the same as the proxy.pac script, namely find out the IP-adress and configure the correct proxy-settings for that network. Otherwise because the computer is always in the same network, it should be easier to configure it once manually.

If anyone has more information on this topic, I would like to read about that.

Markus

It is solved by not using PACs in the first place and instead using a transparent squid proxy or something similar. It may just be a bug in Firefox that is improperly applying (or not applying) the PAC but that would be for the OP to determine. It is acceptable (though poor practice) to require client-side configuration for network access when every machine is managed by the sysadmin, but if people are allowed to use their own machines on the network then mandatory client-side configuration is a very poor choice indeed. Of course, it isn't likely that the OP's school will suddenly change their infrastructure so the point is moot.

The school uses old vision of java and IE 7 still... I use the latest java and slackware current firefox 15.0.1 . I tried chromium but it didn't work either.
so maybe some bug in between firefox and java caused java not to run the script.