Apache Server intermittently consumes all bandwidth

I noticed that my network would become very slow every few minutes. Sometimes RDP sessions would drop and reconnect. Sometimes messenger applications would drop and reconnect. Using some monitoring tools that come with my firewall appliance, I tracked it down to one server on the network. The server is a Windows 2000 server running an xampp installation of Apache Server 2.2 and Tomcat 6.0.20.

I noticed when I turned off Apache, the problem went away. Since I need Apache running though, this could not be the solution. After some reading, I decided to disable PHP. I commented out a couple of lines in a config file to disable it, but this did not fix it. I watched Windows Task Manager and noticed that php-cgi.exe would pop up when the bandwidth problem would occur. I researched php-cgi.exe and found that there are some issues with it running on Windows. I didn't investigate further to find out all the reasons, or even how to fix it because I don't need PHP running on my server. I renamed the php-cgi.exe file and the problem has gone away.

I suspect I could also have commented out more of the php settings in the config file, but renaming the exe file was sufficient.

301 Redirect in Struts

I had the need to do a 301 redirect in my Struts-based web application. I first tried using a redirect="true" attribute in struts-config.xml like this:

<action path="/oldPath" type="com.myapp.controller.MyAction" name="myForm" scope="request" validate="false" parameter="Dispatch">
<forward name="Success" redirect="true" path="/do/newPath">
</forward>

This worked but it turns out it does a 302 redirect (a temporary redirect) as opposed to a permanent redirect, which is a 301. I could not find a way to make this work. What I ended up doing was the following:

[struts-config.xml]
Modified the old action element to use a new MyRedirAction class.

<action path="/oldPath" type="com.myapp.controller.MyRedirAction" name="myForm" scope="request" validate="false" parameter="Dispatch">
</action>

The MyRedirAction class looks like this:

package com.calcxml.controller;

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;

import com.myStuff.base.ServiceException;

public class MyRedirAction extends MyBaseAction {

protected Map getKeyMethodMap() {
Map<string, string=""> map = new HashMap<string, string="">();
return map;
}

public ActionForward unspecified(ActionMapping mapping, ActionForm form, HttpServletRequest request,
HttpServletResponse response) throws ServiceException {
String qs = request.getQueryString();
response.setStatus(301);
if (qs != null) {
response.setHeader("Location", "newPath" + "?" + qs);
} else {
response.setHeader("Location", "newPath");
}
response.setHeader("Connection", "close" );
return null;
}
}


One gotcha that got me was that I assumed incorrectly that the query string (url parameters) would get passed along automatically in the redirect, but that was not the case. I had to add in the additional code to append the query string to the Location header variable.

prunsrv.c error failed creating java

I encounter this error on occasion while setting up servers. The time between each occurrence is just long enough that I forget how to fix it and have to do various google searches. Here is what I have done to fix this:

1. Copy msvcr71.dll from java's bin folder to tomcat's bin folder.
2. Add java's bin directory to windows PATH environment variable.
3. Copy msvcr71.dll from java's bin folder to windows\system32 folder.
4. Make sure your tomcat's pointing to correct jvm.dll folder.

On number 4, what I have done is I run tomcat\bin\tomcat6w.exe which brings up Apache Tomcat Properties dialog box. You can see the java settings on the Java tab. Make sure the Java Virtual Machine is pointing to the correct JVM.