How to remove request blocking on apache reverse proxy after failure of backend before asking backend again?
A bit late answer, but sending it in for refernce
http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass
The key setting is timeout value. Default is 60 seconds, can be set to 0 for always retry.
ProxyPass /path http_//server/ retry=0
On RP configuration what is the value of ProxyTimeout config option? If it is not set, it failbacks to Timeout value.
You won't be able to have a "null" TO (even if it is unnoticeable, Apache tries to connect to backend and it takes time), but setting this value to 1 second may be acceptable.