Hi,
Let me to try to assist with your questions.
Question 1: How can I tell if I have mod_proxy_balancer installed?
Question 2: Should I upgrade to Apache 2.2?
The module mod_proxy_balancer has appeared in Apache 2.1 and later so you will need to upgrade if you would like to use it.
Question 3: How do I upgrade to Apache 2.2?
There are two ways. First is build from sources and second is find rpms for Centos 4 that should be installed on your VPS. I would recommend to try the second way since the first one will require re-building of other components depending on Apache such as PHP, mod_fastcgi etc. But, if the other sites on the server are only static ones and you will not need FastCGI any more, you can choose compiling Apache.
Question 4: I have other web sites (static ones not ROR apps) on this VPS, what impact will upgrading have on them?
Static pages should be working and it might be very scary setup that breaks server from serving static pages.
Question 5: I have Fastcgi installed right now. Should I remove it if I'm going to install Mongrel?
It does not matter as proxying to Mongrel does not affect or depend on Fastcgi.
Question 6: How do I remove Fastcgi?
It depends on how it was installed. More than likely you need to remove Fastcgi rpms.
Question 7: How do I install mod_proxy_balancer?
In 99% cases it will be compiled or provided with Apache 2.2 rpm.
Please reply back if you need further help.
Best Regards,
Vlad
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