Redmine

Here is the configuration that crashes Apache 2.4

# $Id: httpd-proxy-mongrel.conf 166 2010-10-09 09:50:10Z imc $
# Redmine configuration behind Apache 2.2.x and mongrel

# Loading mod_proxy, mod_proxy_http and mod_proxy_balancer

<IfModule !mod_lbmethod_byrequests.c>
    LoadModule lbmethod_byrequests_module lib/modules/mod_lbmethod_byrequests.so
</IfModule>
<IfModule !mod_proxy.c>
    LoadModule proxy_module lib/modules/mod_proxy.so
</IfModule>
<IfModule !mod_proxy_http.c>
    LoadModule proxy_http_module lib/modules/mod_proxy_http.so
</IfModule>
<IfModule !mod_proxy_balancer.c>
    LoadModule proxy_balancer_module lib/modules/mod_proxy_balancer.so
</IfModule>

<Directory E:/data/redmine/public/>
    Options Indexes FollowSymLinks MultiViews
    AllowOverride All
#    Order deny,allow
#    Deny from all
#    Allow from 192.168.20
#   Require ip 192.168.20
    Require all granted
</Directory>

<Proxy *>
#    Order Deny,Allow
#    Deny from all
#    Allow from 192.168.20
#   Require ip 192.168.20
    Require all granted
</Proxy>

ProxyPass / balancer://redmine_cluster/
ProxyPassReverse / balancer://redmine_cluster/

<Proxy balancer://redmine_cluster>
    BalancerMember http://redmine.ourcompany.com:3001
    BalancerMember http://redmine.ourcompany.com:3002
    BalancerMember http://redmine.ourcompany.com:3003
    ProxySet lbmethod=byrequests
</Proxy>

P.S.

ping redmine.ourcompany.com works well; When trying http://redmine.ourcompany.com in Firefox, Firefox waits for a while and then responds that it cannot connect with the server redmine.ourcompany.com.

I found the problem:

mod_slotmem_shm, that is used by mod_proxy_balancer needs DefaultRuntimeDir to be set. I set this in main httpd.conf file, after ServerRoot directive.

Success.