(See also common preferences panel help.)

Proxies Configuration Help

A Proxy allows the machine your Grail Browser is running on to reach the Internet through a Firewall running an HTTP Proxy service. HTTP Proxy Servers such as CERN's httpd server typically run on a special port (the default configuration is port 8080) other than the default port 80, and transparently pass your requests to Internet servers outside of your private network. Generally speaking, once a Proxy service is configured, as a user, you are unaware that it's acting as a relay for your web traffic.

Grail currently supports proxying for the http and ftp protocol schemes. Both of these schemes are proxied via http, which is somewhat counter intuitive.

To enable proxy capability within Grail, select the Manual Proxy Configuration button. You should see the http and ftp proxy server buttons become enabled. One at a time, select the proxy you wish to configure by pressing the newly enabled button on the left and typing in your proxy URL in the entry field to the right. A proxy URL is of the form:

	http://yourproxyserver.yourdomain:specialport

Some examples:

FTP:
```
 http://www.python.org:8080 
```
HTTP:
```
 http://www.gatekeeper.goodschool.edu 
```

You may also wish to configure exceptions to the use of this proxy server if you access a web server internal to your organization. You may add a list of server hosts that are exceptions to the proxy mechanism for these machines by selecting the Proxy Exceptions List button and adding a list of hosts or domain names (or segments) that begin with a leading dot ('.'). Each domain name or host should be separated by a comma, or a single domain name or a single host should be specified without a comma. A domain name or a segment of a domain name that begins with a leading dot, is treated as a wild card and will match all hosts in that domain or segment. For example, if you run grail from inside of a firewall that protects the domain att.com , and all hosts in that domain are reachable to you without a proxy, you may specify .att.com to except all url's that belong to servers in the att.com domain.

An example:

 cnri.reston.va.us, .python.org, www.ftp.org

Proxy support in grail can also be configured using environment variables. The following environment variables replicate the function of the proxies preferences panel and have the side effect of updating preferences to match:

no_proxy: list of comma separated exceptions
http_proxy: proxy URL for HTTP proxying
ftp_proxy: proxy URL for FTP proxying