Smart Cache Manual
Chapter 13 - Troubleshooting

13.1 Browsing problems

I get the following error: 403 Forbidden by rule If I disable the proxy in Netscape and set it for direct Internet connection, the page loads with no problem. How can I fix this?

See section URL blocking, Section 5.6

I am getting following message, how can i get it off?

     Warning: Page has Expired The page you requested was created using
     information you submitted in a form. This page is no longer available. As a
     security precaution, Internet Explorer does not automatically resubmit your
     information for you.
     
     To resubmit your information and view this Web page, click the Refresh
     button.

You can't. HTTP proxies do not cache POST requests.

I get the following error: 501 Protocol FTP is not directly supported

Smart Cache supports caching of FTP transfers only if you have set http_proxy to server, which supports FTP via HTTP. Many ISPs have it. If you do not know any, set up your browser to not use Smart Cache for FTP transfers. See also Configuring a Web browser, Section 4.3, Using Smart Cache for non-HTTP protocols, Section 7.8.

I sometimes find SmartCache alters the behaviour of some pages; to be sure, I then disable the proxy setting in Netscape and get a different result. Could this be related to Java programs within the page?

Smart Cache do not alter received pages/data in any way; It changes just HTTP headers (when sending to server or to client). If you see different page, it means that remote server sent you a different page. Right question is: ,,why server send me a different page?''

Why server sent me a different page when I am using Smart Cache?

Because Smart Cache modified HTTP request from your browser. The biggest effect on sending different pages has User-Agent: header. If you are using fake_user_agent disable it.

Which configuration options affects modifying my requests?

1. fake_user_agent changes your web browser identity. Some server sends slightly modified versions of pages to some browsers. [7]

2. remove_pragma_no_cache When set, 'Pragma' header will be deleted in outgoing requests. (Increases sucessfull IMS hit rate)

3. referer_hack dynamically changes Referer header.

4. fake_referer changes Referer header to specified String. If fake_referer is used, referer_hack is ignored.

5. fake_cookie and cookies filter can replace/remove cookies.

Reloads in my browser don't work anymore!

Look at directive default_refresh_pattern. First number is for ignoring reload requests. If there is bigger number than zero, reloads of younger page than that are forbidden. If you don't want to ignore reload requests, set it to zero, but better is to use some small value, such as 1-3 minutes for avoiding reloads forced by browser itself. See also Configurating refresh patterns, Section 7.2 [8]

Automatic dialing does not work any more. How do I fix it?

Some browsers (such as MSIE-4) can be configured to dial your ISP automatically when you click on a link, but this feature gets disabled if you specify a proxy running on your own computer (with address localhost or 127.0.0.1) because these addresses don't require dialing. Smart Cache knows nothing about dialing, so it doesn't work. To make automatic dialing work, make up a name such as smart.cache and use it in the proxy settings instead of localhost, and then add 127.0.0.1 smart.cache to file c:\windows\hosts (if there already is a line beginning with 127.0.0.1, just add smart.cache at the end of it.) This should also work with Netscape Communicator 4 on machines where MSIE-4 has been installed.

Smart Cache do not cache any data from secure server! What about to support https?

Smart Cache supports https now, but these pages can not be cached because there are ENCRYPTED! Smart Cache do not even knows URLs of encrypted requests. Blocking entire HTTPS site via fail.cnf works. If you have direct connection to Internet you will not get any extras when using SC as https proxy.

13.2 Start up problems

I got message "Command not found" from OS.

Add Java runtime directory to your PATH if it was not done by Java installation program. See also Checking the Java installation, Section 3.4

I got message "Class not found" from Java runtime.

1. Are .class files in your current directory?

2. Do you unpack scache.zip with utility with long names support?

3. Are .class files located on disk, which supports long names?

4. Do not write .class extension when running smartcache. DO NOT RUN java scache.class !

5. Do you have at least Java 1.1 version ? Type java -version for report.

6. Do you have current directory . listed in environment variable CLASSPATH? If not add -cp . option to Java runtime.

7. If you are using OS/2, Smart Cache will not operate on FAT drives (no long names).

See also Generic installation from .zip file, Section 3.6

Smart Cache ends with fatal error Can not bind to my port

This may be caused by one of following things: [9]

1. Smart Cache is already running or

2. Other application runs on the Smart Cache port. Try telnet to it. If you do not get Connection refused. error, change port in configuration file.

3. Address specified as BindAddress is not your local IP address. [10]

4. You do not have the loopback interface configured. (Very common problem on OS/2 machines) Type: ifconfig lo 127.0.0.1

13.3 Memory usage problems

Java runtime eats too much of my memory!

add -ms1m (start JVM with 1MB memory pool) option, before scache to command line for invoking java interpreter. If this do not helps too much, try different Java runtime.

Java uses on my Linux much more memory than written in this document.

It is normal. Java tries to use free memory when it is available. If this memory will be required by other applications kernel just swaps it out and it will be never (rarely) loaded back. For forcing kernel to do that (free memory is good for dynamic disk cache) use some utility, such as my swapout, which allocates all available physical memory, touches this memory and exits.

13.4 Run time problems

I can't connect to Smart Cache from other computers!

See Setting the bindaddress, Section 9.10

Smart Cache Manual