6.4 Troubleshooting the Apache HTTP Server

This section describes some issues you might experience with Apache HTTP Server and provides suggestions for resolving or avoiding them. For additional troubleshooting information, see the Novell Technical Support Knowledgebase.

6.4.1 Apache Server Errors after Using the HTTP Server Option in YaST

If you use the HTTP Server option in YaST to manage Apache or virtual hosts, the option can overwrite essential OES settings and load the wrong modules, which breaks the default Apache HTTP Server setup. See TID 7002562 in the Novell Knowledgebase.

If you have used the HTTP Server option in YaST and Apache is no longer working, recover the OES default Apache HTTP Server setup by doing the following:

As the root user, open the /etc/sysconfig/apache2 file in a text editor and modify the following directives:
- Proxy module: In the APACHE_MODULES= line in the file, ensure that the proxy module is listed before the proxy_ajp module. For example (some modules are not listed for ease of reading the example):
```
APACHE_MODULES="cgi dir rewrite ssl proxy proxy_ajp ssl"
```
- SSL module: In the APACHE_MODULES= line in the file, ensure that the ssl module is listed. For example (some modules are not listed for ease of reading the example):
```
APACHE_MODULES="cgi dir rewrite ssl proxy proxy_ajp ssl"
```
- Prefork mode: Apache should run in prefork mode rather than worker mode. To force this, ensure that the APACHE_MPM="" line is set to "prefork". For example:
```
APACHE_MPM="prefork"
```
- SSL: Ensure secure communications by enabling the SSL flag. For example:
```
APACHE_SERVER_FLAGS="SSL"
```
Gracefully restart Apache to apply the changes. As the root user, enter the following command at a console prompt:
```
              rcapache2 graceful
            
```

6.4.2 Files Downloaded from NetStorage Are 0 Bytes

After you lock down ciphers for an Apache HTTP Server to use only the strongest SSL ciphers, all of the files downloaded from NetStorage are 0 bytes in size.

NetStorage might not work as expected if you lock down Apache HTTP Server to disallow low and medium SSL ciphers. Try allowing medium SSL cipher settings to see if that is sufficient, then add back low cipher settings if necessary.

For other SSL cipher configuration options, see SSL/TLS Strong Encryption: How-To at Apache.org.