concept of fali over sqid server
 

Now that i have setup a proxy server, as a next step i want to run it in fail-over high availability mode, so that if one proxy is down due
to any reason, second proxy should automatically be up and start
serving requests.

any help in shape of articles/steps would be highly appreciated.

Push the resilience back to the client with a decent proxy.pac script, no need to do anything on the server side, just have to totally normal standalone servers. There also is a script around the net called something like the megaproxy script which is a proxy.pac script which does some url hashing to load balance proxies automatically from a browser. nice.

And you really don't want such details in your signature, hello spammers!!

Well Chris no its not gonna help me. Its not a solution, what i am looking for like
primary and secondary server concept.

it is a solution, and it's the most resilient and simplest solution you're going to find. Squid clearly can't do what you want within itself, and you'd need some form of high availability subsystem, like that which you would find on linux-ha.org. A lot of extra work for very very little benefit over a simple proxy.pac.