Re: [squid-users] origin server status check before forwarding requests

 On Sun, 18 Sep 2011 18:48:12 +0530, Deepak Rao wrote:
> Hi,
>
> I am using squid in reverse proxy mode. So far, we were using
> cache_peer and cache_peer_access to forward the request to origin
> server, and there were 2 origin servers configured for load balance
> and HA. Squid checks the health of these origin servers before
> forwarding the request to one i.e., if one of the origin server is
> down, all the requests landed up on the 'live' server, thus ensuring
> no request is failed.
>
> Now, we have a requirement to rewrite the request url (and hostname
> in
> the url) before forwarding the request to origin server. Hence, we
> are
> using url_rewrite_program instead of cache_peer*. Is there a way to
> achieve the 'health check and only then forward' feature inherent in
> cache_peer configuration, in case of url_rewrite too?
>
> Thanks,
> Deepak

 Yes. Use both re-write and cache_peer. All re-write does is create a
 duplicate request with different URL line to be sent to the server,
 instead of passing the original request out.

 You may not need to wade through the performance overhead involved with
 re-write. Look at whether your suqid supports the forcedomain= option on
 cache_peer. This will avoid the need to clone the whole request. You
 will still encounter all the other problems re-write has with embedded
 URLs and internal hostnames being sent out to the client.

 Amos
Received on Sun Sep 18 2011 - 22:58:06 MDT