Mod_proxy_balancer mod_rewrite permission issue

Server Mongrel
1

I started the mongrel_cluster and tried to use the RewriteRule to
forward
the requests to proxy_balancer just as the
http://mongrel.rubyforge.org/docs/apache.html said.
When I visited my site from a remote computer, I always got the error
messages “Forbidden, You don’t have permission to access / on this
server.”

Finally, I added the “Allow from all” property (in the vhost config
file),
just like this:
<Proxy balancer://mongrel_cluster>
BalancerMember http://127.0.0.1:8001
BalancerMember http://127.0.0.1:8002
BalancerMember http://127.0.0.1:8003

    Order allow,deny
    Allow from all
then the "Forbidden" problem was solved. The "all" could not be changed to "127.0.0.1" or others. I guest this should be related with the implement detail of the mod_rewrite.

My question is, could this “Allow from all” be a latent security
problem?
and is there anybody faced the same issue?
Could I miss something through the configuration or did the
mongrel-apache
document miss something?

I am sorry my English is not very good.

Best wishes everyone,

Alfie ZHU

2

I searched and found someone got the same problem 1 year ago:
http://rubyforge.org/pipermail/mongrel-users/2006-December/002594.html
But it seams he finally used the ProxyPass instead of RewriteRule, and
did
not actually solve the problem.

I hope my solution will give some possibility to fixing the same
problem.