What happens when the policy server crashes

2009-06-03 Thread Rob Tanner
Hi,

We have some email policies that we want to implement and it looks like a
policy server is the perfect tool.  We have two edge servers on which we
want to implement the policies.  My thought is to build a threaded server in
Java and run it actually one the machine that the databases it will consult
are already running.  My question is what happens if for any reason the
policy server hangs, crashes, etc, and stops accepting connections.  Does
Postfix also hang and stop processing mail or does Postfix simply timeout
and is the timeout length a settable parameter in main.cf?

Thanks,
Rob



--
Rob Tanner
UNIX Services Manager
Linfield College, McMinnville Oregon
503-883-2558



Re: What happens when the policy server crashes

2009-06-03 Thread Wietse Venema
Rob Tanner:
 Hi,
 
 We have some email policies that we want to implement and it looks like a
 policy server is the perfect tool.  We have two edge servers on which we
 want to implement the policies.  My thought is to build a threaded server in
 Java and run it actually one the machine that the databases it will consult
 are already running.  My question is what happens if for any reason the
 policy server hangs, crashes, etc, and stops accepting connections.  Does
 Postfix also hang and stop processing mail or does Postfix simply timeout
 and is the timeout length a settable parameter in main.cf?

Postfix detects connection timeout or connection failure and tries
to reconnect a few times. It then sends a 4xx reply to the client
so that the client can try again later.

The default setting is:

smtpd_policy_service_timeout = 100s

You'll want to use a robust policy server (like, one that is
restarted) and a monitor that checks if it is still responsive.

Wietse